Important Maths Questions for RRB Group D Exam, Check Details

Important Maths Questions for RRB Group D Exam: The RRB Group D Examination is conducted by the Railway Recruitment Board to recruit candidates for various Group D posts. One of the most important sections in the Group D exam is mathematics. The important topics that candidates must study for mathematics include Square Root, Percentage, Tabular Graph, Pie Chart, LCM & HCF, Divisibility & Remainder, Partial Speed, Relative Speed, and more. In this article, we will provide some important questions related to mathematics for the RRB Group D Exam 2025.

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Important Maths Questions for RRB Group D Examination 2025

We have given below the most common mathematics questions along with the answers for the RRB Group D Examination 2025. Candidates will have an understanding of the difficulty level of the questions asked in the examination:

1. Number System & Simplification

1. Find the LCM of 24, 36, and 48.
2. Find the HCF of 56 and 84.
3. The LCM and HCF of two numbers are 180 and 15, respectively. If one number is 45, find the other.
4. Evaluate: 25+310−415\frac{2}{5} + \frac{3}{10} – \frac{4}{15}
5. Find the smallest number that, when divided by 35, 56, and 91 leaves the same remainder 7.
6. Simplify: 34÷916×827\frac{3}{4} \div \frac{9}{16} \times \frac{8}{27}
7. If 5x=1255^x = 125, find xx.
8. Find the remainder when 789 is divided by 13.
9. Write 0.1875 as a fraction in simplest form.
10. Find the value of 81+273\sqrt{81} + \sqrt[3]{27}.

2. Algebra

11. Solve: 5x−7=3x+55x – 7 = 3x + 5
12. If 3x+2=113x + 2 = 11, find xx.
13. Find the value of xx if 2×2−8=02x^2 – 8 = 0.
14. Simplify: (x+3)(x−3)(x + 3)(x – 3)
15. If a=5a = 5 and b=2b = 2, find a2+2ab+b2a^2 + 2ab + b^2.
16. If 2x+3y=122x + 3y = 12 and x−y=2x – y = 2, find xx and yy.
17. Solve: x+32=5\frac{x+3}{2} = 5.
18. Factorise: x2+5x+6x^2 + 5x + 6.
19. If x+1x=5x + \frac{1}{x} = 5, find x2+1x2x^2 + \frac{1}{x^2}.
20. Solve for yy: 7y−14=07y – 14 = 0.

3. Percentage & Profit-Loss

21. Find 25% of 640.
22. If a number increases from 80 to 100, find the percentage increase.
23. A trader bought an article for ₹250 and sold it for ₹300. Find his profit percentage.
24. A shopkeeper sold an article at 20% loss. If its selling price was ₹800, find its cost price.
25. If a person earns ₹15,000 per month and spends 40% on rent, how much does he spend on rent?
26. The population of a town increased by 10% in one year. If the present population is 66,000, find the population last year.
27. A TV was sold for ₹12,000 at a profit of 25%. Find the cost price.
28. An item costs ₹500. A shopkeeper gives a discount of 10%. Find the selling price.
29. Find the loss when an article bought for ₹900 is sold for ₹750.
30. If the cost price of an article is ₹200 and the profit is ₹50, find the profit percentage.

4. Ratio & Proportion

31. The ratio of ages of A and B is 3:5. If the sum of their ages is 40 years, find their ages.
32. Divide ₹900 between A and B in the ratio 2:1.
33. If 2x=515\frac{2}{x} = \frac{5}{15}, find xx.
34. Two numbers are in the ratio 4:7. If their sum is 77, find the numbers.
35. A and B can finish a work in the ratio of 5:3 days. If A takes 10 days, how many days will B take?
36. If x:y=3:4x : y = 3 : 4 and y:z=2:5y : z = 2 : 5, find x:zx : z.
37. Divide ₹2,400 among A, B, and C in the ratio 3:2:5.
38. If 5 kg rice costs ₹200, find the cost of 8 kg rice.
39. Find the mean proportional between 16 and 64.
40. If the ratio of the number of boys to girls is 5:3 and there are 40 boys, find the number of girls.

5. Time, Speed, Distance & Work

41. A train covers 240 km in 4 hours. Find its speed.
42. If a car travels at 60 km/h, how much time will it take to travel 150 km?
43. A man walks at 5 km/h. How long will he take to cover 20 km?
44. A and B can complete a work in 12 days and 15 days respectively. In how many days will they complete the work together?
45. If 12 men can do a work in 8 days, how many men are required to complete it in 6 days?
46. A cyclist covers 45 km in 3 hours. Find his speed.
47. If a car runs at 80 km/h, how far will it go in 2.5 hours?
48. A man can row 12 km downstream in 3 hours and upstream in 4 hours. Find the speed in still water.
49. A train 180 m long passes a pole in 6 seconds. Find its speed in km/h.
50. If A can do a piece of work in 10 days and B can do it in 15 days, in how many days will both finish the work together?

6. Simple & Compound Interest

51. Find the simple interest on ₹8,000 at 12% per annum for 2 years.
52. What is the compound interest on ₹5,000 for 2 years at 10% per annum?
53. The simple interest on a sum of money for 3 years at 8% p.a. is ₹2,400. Find the principal.
54. Find the amount after 3 years on ₹4,000 at 5% p.a. compound interest.
55. Find the principal if the simple interest for 5 years at 6% p.a. is ₹3,000.
56. Find the difference between compound interest and simple interest on ₹10,000 at 10% p.a. for 2 years.
57. If the simple interest on a sum at 7% p.a. for 4 years is ₹2,800, find the sum.
58. The compound interest on ₹20,000 at 8% p.a. for 1 year is?
59. Find the time if ₹4,000 becomes ₹4,800 at 10% p.a. simple interest.
60. Find the simple interest on ₹15,000 at 5% p.a. for 9 months.

7. Mensuration

61. Find the perimeter of a rectangle with length 25 m and breadth 15 m.
62. Find the area of a square whose side is 12 cm.
63. Find the volume of a cuboid of length 5 m, breadth 4 m, and height 3 m.
64. The radius of a circle is 14 cm. Find its circumference.
65. The base of a triangle is 20 cm, height 15 cm. Find its area.
66. Find the volume of a sphere of radius 7 cm.
67. Find the total surface area of a cube of side 8 cm.
68. Find the diagonal of a rectangle whose length is 24 cm and breadth is 7 cm.
69. Find the perimeter of an equilateral triangle of side 18 cm.
70. Find the curved surface area of a cylinder of radius 7 cm and height 20 cm.

8. Geometry & Trigonometry

71. The sum of angles of a triangle is?
72. In a right-angled triangle, if one angle is 30°, find the other acute angle.
73. Find the value of sin⁡30∘\sin 30^\circ.
74. Find the value of cos⁡60∘\cos 60^\circ.
75. If tan⁡θ=34\tan \theta = \frac{3}{4}, find sin⁡θ\sin \theta.
76. In a triangle, if two angles are 70° and 50°, find the third angle.
77. The height of a building is 40 m. A ladder reaches the top at a distance of 30 m from its base. Find its length.
78. If sin⁡θ=0.5\sin \theta = 0.5, find θ\theta.
79. Find the perimeter of a square whose diagonal is 10 cm.
80. A regular hexagon has side length 6 cm. Find its perimeter.

9. Data Interpretation

81. The marks obtained by 5 students are 45, 50, 55, 60, 65. Find the average marks.
82. A shopkeeper sold 120 kg rice in January and 150 kg in February. Find the percentage increase.
83. The monthly income of a person is ₹25,000. He spends ₹15,000. Find his savings percentage.
84. If the cost of 10 pens is ₹150, find the cost of 15 pens.
85. In a class of 40 students, 25 are boys. Find the percentage of girls.
86. The production of a factory in 2018 was 2,000 units and in 2019 it was 2,400 units. Find the percentage change.
87. The average age of 5 members of a family is 30 years. Find their total age.
88. In a survey, 60% people like tea, 30% coffee, and the rest neither. Find the percentage of people who like neither.
89. A student scored 420 marks out of 600. Find his percentage.
90. The population of a city is 2,00,000. If it increases by 5% in a year, find the population next year.

10. Mixed Practice

91. If the selling price is ₹840 and the profit is 20%, find the cost price.
92. A man covers a distance of 15 km at 5 km/h and returns at 3 km/h. Find his average speed.
93. Find the simple interest on ₹9,000 at 4% p.a. for 4 years.
94. If x=5\sqrt{x} = 5, find xx.
95. Find the smallest number divisible by 15, 20, and 25.
96. A train runs at 72 km/h. Find the distance it covers in 25 minutes.
97. The perimeter of a square is 48 cm. Find its area.
98. The height of a cone is 24 cm and its radius is 7 cm. Find its volume.
99. If 12 men can complete a work in 10 days, how many days will 8 men take?
100. A student gets 60% marks in 500. Find his marks.

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Answers for RRB Group D Mathematics Questions

The answers for the above-mentioned questions are given below accordingly:

1. LCM(24, 36, 48) = 144.
   Prime factors → 24=23⋅324=2^3\cdot3, 36=22⋅3236=2^2\cdot3^2, 48=24⋅348=2^4\cdot3; LCM =24⋅32=144=2^4\cdot3^2=144.
2. HCF(56, 84) = 28. (common highest factor)
3. Other number = 60.
   LCM×HCF=180×15=product of numbers⇒270045=60\text{LCM}\times \text{HCF} = 180\times15 = \text{product of numbers} \Rightarrow \frac{2700}{45}=60.
4. 25+310−415=1330. \frac{2}{5}+\frac{3}{10}-\frac{4}{15} = \boxed{\frac{13}{30}}.
5. Smallest number = 3647.
   If remainder is 7 for 35, 56, 91, then N−7N-7 is divisible by all → N=LCM⁡(35,56,91)+7=3640+7N= \operatorname{LCM}(35,56,91)+7=3640+7.
6. 34÷916×827=34×169×827=3281. \frac{3}{4}\div\frac{9}{16}\times\frac{8}{27} = \frac{3}{4}\times\frac{16}{9}\times\frac{8}{27}=\boxed{\frac{32}{81}}.
7. 5x=125=53⇒x=3.5^x=125=5^3\Rightarrow \boxed{x=3}.
8. Remainder = 9. ( 789=13×60+9789=13\times60 + \boxed{9})
9. 0.1875=3160.1875=\boxed{\tfrac{3}{16}} (divide by 625).
10. 81+273=9+3=12.\sqrt{81}+\sqrt[3]{27}=9+3=\boxed{12}.

Algebra

11. 5x−7=3x+5⇒2x=12⇒x=6.5x-7=3x+5\Rightarrow 2x=12\Rightarrow \boxed{x=6}.
12. 3x+2=11⇒3x=9⇒x=3.3x+2=11\Rightarrow 3x=9\Rightarrow \boxed{x=3}.
13. 2×2−8=0⇒x2=4⇒x=±2.2x^2-8=0\Rightarrow x^2=4\Rightarrow \boxed{x=\pm2}.
14. (x+3)(x−3)=x2−9.(x+3)(x-3)=\boxed{x^2-9}.
15. a2+2ab+b2=(a+b)2=(5+2)2=49.a^2+2ab+b^2=(a+b)^2=(5+2)^2=\boxed{49}.
16. {2x+3y=12x−y=2⇒x=185, y=85.\begin{cases}2x+3y=12\\ x-y=2\end{cases}\Rightarrow x=\tfrac{18}{5},\, y=\tfrac{8}{5}.

17. x+32=5⇒x+3=10⇒x=7.\frac{x+3}{2}=5\Rightarrow x+3=10\Rightarrow \boxed{x=7}.
18. x2+5x+6=(x+2)(x+3).x^2+5x+6=\boxed{(x+2)(x+3)}.
19. x+1x=5⇒x2+1×2=52−2=23.x+\frac1x=5\Rightarrow x^2+\frac1{x^2}=5^2-2=\boxed{23}.
20. 7y−14=0⇒y=2.7y-14=0\Rightarrow \boxed{y=2}.

Percentage & Profit–Loss

21. 25% of 640=160.25\%\text{ of }640= \boxed{160}.
22. Increase =100−8080×100=25%.= \frac{100-80}{80}\times100=\boxed{25\%}.
23. Profit %=300−250250×100=20%.\%=\frac{300-250}{250}\times100=\boxed{20\%}.
24. SP=800SP=800 at 20%20\% loss → CP=8000.8=1000.CP=\frac{800}{0.8}=\boxed{1000}.
25. Rent =40%=40\% of 15000 =₹6000.=\boxed{₹6000}.
26. Last year =660001.10=60000.=\frac{66000}{1.10}=\boxed{60000}.
27. SP=12000SP=12000 at 25%25\% profit → CP=120001.25=₹9600.CP=\frac{12000}{1.25}=\boxed{₹9600}.
28. 500 with 10% discount → SP=500−50=₹450.SP=500-50=450
29. Loss =900−750=₹150.=900-750=\boxed{₹150}.
30. Profit %=50200×100=25%.\%=\frac{50}{200}\times100=\boxed{25\%}.

Ratio & Proportion

31. 3k+5k=40⇒k=53k+5k=40\Rightarrow k=5. Ages A=15,  B=25\boxed{A=15,\;B=25}.
32. Ratio 2:12:1 → shares ₹600, ₹300.\boxed{₹600,\,₹300}.
33. 2x=515=13⇒x=6.\frac{2}{x}=\frac{5}{15}=\frac{1}{3}\Rightarrow \boxed{x=6}.
34. 4k+7k=77⇒k=7⇒28,  49.4k+7k=77\Rightarrow k=7\Rightarrow \boxed{28,\;49}.
35. Days ratio 5:35:3. If A=10=5k⇒k=2⇒B=6A=10=5k\Rightarrow k=2\Rightarrow B=\boxed{6} days.
36. x:y=3:4,  y:z=2:5⇒y=4x:y=3:4,\;y:z=2:5\Rightarrow y=4 common → z=10z=10. Hence x:z=3:10.x:z=\boxed{3:10}.
37. Total parts =10=10. Shares ₹720,₹480,₹1200.\boxed{₹720, ₹480, ₹1200}.
38. 5 kg→₹200⇒1 kg=₹40⇒8 kg=₹320.5\text{ kg}\to₹200\Rightarrow 1\text{ kg}=₹40\Rightarrow 8\text{ kg}= \boxed{₹320}.
39. Mean proportional =16⋅64=32.=\sqrt{16\cdot64}=\boxed{32}.
40. Boys:girls =5:3=5:3, boys =40=5k⇒k=8⇒24=40=5k\Rightarrow k=8\Rightarrow \boxed{24} girls.

Time, Speed, Distance & Work

41. 240/4=60240/4=\boxed{60} km/h.
42. t=150/60=2.5t=150/60=\boxed{2.5} h.
43. t=20/5=4t=20/5=\boxed{4} h.
44. 1T=112+115=960=320⇒T=203 \frac{1}{T}=\frac{1}{12}+\frac{1}{15}=\frac{9}{60}=\frac{3}{20}\Rightarrow T=\boxed{\frac{20}{3}} days.
45. Work =12×8=96=12\times8=96 man-days. In 6 days → 96/6=1696/6=\boxed{16} men.
46. 45/3=1545/3=\boxed{15} km/h.
47. 80×2.5=20080\times2.5=\boxed{200} km.
48. Down =12/3=4=12/3=4, up =12/4=3=12/4=3 → still water =4+32=3.5=\frac{4+3}{2}=\boxed{3.5} km/h.
49. Speed =180 m/6 s=30 m/s=30×185=108=180\text{ m}/6\text{ s}=30\text{ m/s}=30\times\frac{18}{5}=\boxed{108} km/h.
50. 1T=110+115=16⇒T=6 \frac{1}{T}=\frac{1}{10}+\frac{1}{15}=\frac{1}{6}\Rightarrow T=\boxed{6} days.

Simple & Compound Interest

51. SI=8000×12100×2=₹1920.SI=8000\times\frac{12}{100}\times2=\boxed{₹1920}.
52. A=5000(1.1)2=₹6050⇒CI=₹1050.A=5000(1.1)^2=₹6050\Rightarrow CI=\boxed{₹1050}.
53. P=SIRT=24000.08×3=₹10,000.P=\frac{SI}{RT}=\frac{2400}{0.08\times3}=\boxed{₹10{,}000}.
54. A=4000(1.05)3=₹4630.50A=4000(1.05)^3=\boxed{₹4630.50} (approx).
55. P=30000.06×5=₹10,000.P=\frac{3000}{0.06\times5}=\boxed{₹10{,}000}.
56. SI=₹2000SI=₹2000, CI=₹2100CI=₹2100 → difference ₹100.\boxed{₹100}.
57. P=28000.07×4=₹10,000.P=\frac{2800}{0.07\times4}=\boxed{₹10{,}000}.
58. CI=20000×8100=₹1600CI=20000\times\frac{8}{100}= \boxed{₹1600} (1 year).
59. 4000→48004000 \to 4800. SI=800=4000×0.10×t⇒t=2SI=800=4000\times0.10\times t \Rightarrow t=\boxed{2} years.
60. SI=15000×5100×912=₹562.50.SI=15000\times\frac{5}{100}\times\frac{9}{12}=\boxed{₹562.50}.

Mensuration

61. Perimeter =2(l+b)=2(25+15)=80=2(l+b)=2(25+15)=\boxed{80} m.
62. Area =122=144=12^2=\boxed{144} cm².
63. Volume =lbh=5⋅4⋅3=60=lbh=5\cdot4\cdot3=\boxed{60} m³.
64. Circumference =2πr=28π=88 cm (approx)=2\pi r=28\pi=\boxed{88\text{ cm (approx)}} (exact 28π28\pi).
65. Area =12bh=12⋅20⋅15=150=\tfrac12 bh=\tfrac12\cdot20\cdot15=\boxed{150} cm².
66. Volume sphere =43πr3=13723π≈1436.8=\tfrac{4}{3}\pi r^3=\tfrac{1372}{3}\pi\approx\boxed{1436.8} cm³.
67. TSA cube =6a2=6⋅82=384=6a^2=6\cdot8^2= \boxed{384} cm².
68. Diagonal =242+72=625=25=\sqrt{24^2+7^2}=\sqrt{625}=\boxed{25} cm.
69. Perimeter equilateral =3a=3⋅18=54=3a=3\cdot18=\boxed{54} cm.
70. CSA cylinder =2πrh=2π⋅7⋅20=280π≈879.6=2\pi rh=2\pi\cdot7\cdot20=280\pi\approx\boxed{879.6} cm².

Geometry & Trigonometry

71. 180∘\boxed{180^\circ}.
72. 60∘\boxed{60^\circ} (since 90∘−30∘90^\circ-30^\circ).
73. 12\boxed{\tfrac{1}{2}}.
74. 12\boxed{\tfrac{1}{2}}.
75. tan⁡θ=34⇒sin⁡θ=35.\tan\theta=\frac{3}{4}\Rightarrow \sin\theta=\frac{3}{5}.
76. Third angle =180−(70+50)=60∘.=180-(70+50)=\boxed{60^\circ}.
77. Ladder =402+302=2500=50=\sqrt{40^2+30^2}=\sqrt{2500}=\boxed{50} m.
78. sin⁡θ=0.5⇒θ=30∘\sin\theta=0.5\Rightarrow \boxed{\theta=30^\circ} (acute).
79. Diagonal d=10⇒s=102=52d=10\Rightarrow s=\frac{10}{\sqrt2}=5\sqrt2; perimeter =4s=202≈28.28=4s= \boxed{20\sqrt2\approx28.28} cm.
80. Perimeter hexagon =6×6=36=6\times6=\boxed{36} cm.

Data Interpretation

81. Average =45+50+55+60+655=55=\frac{45+50+55+60+65}{5}=\boxed{55}.
82. Increase %=150−120120×100=25%.\%=\frac{150-120}{120}\times100=\boxed{25\%}.
83. Savings =25000−15000=10000⇒1000025000×100=40%.=25000-15000=10000 \Rightarrow \frac{10000}{25000}\times100=\boxed{40\%}.
84. Unit cost =15⇒15 pens=₹225.=15\Rightarrow 15\text{ pens}= \boxed{₹225}.
85. Girls =40−25=15⇒1540×100=37.5%.=40-25=15\Rightarrow \frac{15}{40}\times100=\boxed{37.5\%}.
86. Change %=2400−20002000×100=20%.\%=\frac{2400-2000}{2000}\times100=\boxed{20\%}.
87. Total age =30×5=150=30\times5=\boxed{150} years.
88. Tea 60%60\%, coffee 30%30\% → neither =100−90=10%.=100-90=\boxed{10\%}.
89. 420600×100=70%.\frac{420}{600}\times100=\boxed{70\%}.
90. Next year =200000×1.05=210000.=200000\times1.05=\boxed{210000}.

Mixed Practice

91. CP=SP1+0.20=8401.2=₹700.CP=\frac{SP}{1+0.20}=\frac{840}{1.2}=\boxed{₹700}.
92. Average speed (equal distances): 2aba+b=2⋅5⋅35+3=3.75 \frac{2ab}{a+b}=\frac{2\cdot5\cdot3}{5+3}=\boxed{3.75} km/h.
93. SI=9000×4100×4=₹1440.SI=9000\times\frac{4}{100}\times4=\boxed{₹1440}.
94. x=5⇒x=25.\sqrt{x}=5\Rightarrow \boxed{x=25}.
95. LCM(15,20,25)=300.\text{LCM}(15,20,25)=\boxed{300}.
96. 7272 km/h =20=20 m/s; 2525 min =1500=1500 s → distance =20×1500=30=20\times1500=\boxed{30} km.
97. Perimeter =48⇒s=12⇒Area=122=144=48\Rightarrow s=12\Rightarrow \text{Area}=12^2=\boxed{144} cm².
98. Cone V=13πr2h=13π⋅72⋅24=392π≈1231.5V=\tfrac13\pi r^2h=\tfrac13\pi\cdot7^2\cdot24=392\pi\approx\boxed{1231.5} cm³.
99. Work =12×10=120=12\times10=120 man-days → 88 men take 120/8=15120/8=\boxed{15} days.
100. 60%60\% of 500 =300=\boxed{300} marks.

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RRB Group D Exam Pattern

The RRB Group D Exam Pattern consists of four important sections – General Science, Mathematics, General Intelligence & Reasoning, General Awareness, and Current Affairs. The mathematics section consists of 25 questions, each carrying one mark. The details are given below:

• Duration: 90 minutes
• Marking Scheme: +1 for every correct answer
• Negative Marking: -1/3 for every wrong answer
• Total Questions: 100

Subjects	Questions	Marks
General Science	25	25
Mathematics	25	25
General Intelligence & Reasoning	30	30
General Awareness and Current Affairs	20	20
Total	100	100

We hope you understood the level of difficulty of the Important Maths Questions asked in the Group D examination for mathematics. To read more such articles, visit our Oliveboard website.

FAQs

Q.1 What are the important topics in Mathematics for RRB Group D Examination?

Ans. The important topics that candidates must study for mathematics include Square Root, Percentage, Tabular Graph, Pie Chart, LCM & HCF, Divisibility & Remainder, Partial Speed, Relative Speed, and more.

Q.2 How many marks does the mathematics section hold?

Ans. The mathematics section consists of 25 questions, each carrying one mark.

Q.3 Should I attempt mock tests regularly for the Group D examination?

Ans. Yes, it is recommended to attempt mock tests regularly for the Group D Examination.

Q.4 What are the total marks for the RRB Group D Examination?

The total marks for the RRB Group D exam are 100.

Q.5 Is there any negative marking in the Mathematics section?

Ans. Yes, there is a negative marking of -1/3 for every wrong answer in the mathematics section.