Practice Questions for Decimals and Fractions for RRB NTPC

Decimal and fraction questions for RRB NTPC is one of those topics which can be solved quickly and if done with accuracy will fetch you marks.

Decimals and fractions are part of each other and closely related. Some important things to be noted are that there are some things which, if remembered correctly will help students solve Decimal and fraction questions for RRB NTPC questions more quickly. For example, 0.25 can be written as 1/4 which will help solve questions.

Decimal and Fraction questions for RRB NTPC 

Here are some practice questions which will help you get an idea on how to solve decimal and fraction questions for RRB NTPC effectively.

Q1. Find a fraction in which if the numerator is tripled and the denominator is increased by 9 fractions becomes 3/7. If the denominator is tripled and the numerator is increased by 3 then it becomes 1/3.

a) 2/3

b) 1/2

c) 2/5

d) 2/7

Answer key: c

Solution:

Let the fraction be m/n

Given, 3m/(n+9) = 3/7

21m = 3n + 27                  — (1)

and (m+3)/3n = 1/3

3m + 9 = 3n

3m = 3n – 9                     — (2)

Solving (1) and (2) we get,

m = 2 and n = 5

So the fraction = 2/5

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Q2. Express 1. 123123.. into (p/q) form.

a) 374/333

b) 382/333

c) 371/330

d) 367/330

Answer key: a

Solution:

Let X = 1. 123123              .. (I)

1000X = 1123. 123123       .. (II)

(II) – (I) gives:

999X = 1122

X = 374/333

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Q3. Calculate the fractional value of 1.212121….

a) 1(7/33)

b) 1(5/33)

c) 1(9/11)

d) 1(4/11)

Answer key: a

Solution:

Let X = 1.212121               ….(i)

Then, 100X = 121.2121       …(ii)

On subtracting (i) by (ii), we get

99X = 120

Then, X = 1(7/33)

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Q4. What is the value of: (4.2*3.47 – 4.2*1.22)/(0.7*2.4 + 2.4*1.68 – 3.612) ?

a) 3

b) 2.5

c) 5

d) 4.5

Answer key: d

Solution:

(4.2*3.47 – 4.2*1.22)/(0.7*2.4 + 2.4*1.68 – 3.612)

= (4.2(3.47 – 1.22))/(1.4(1.2 + 2.4*1.2 – 2.58))

= (3*2.25)/1.5

= 4.5

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Q5. What is the average of the reciprocal of a and b?

a) (a+b)/ab

b) (a+b)/2ab

c) 2(a+b)/ab

d) (2a+b)/ab

Answer key: b

Solution:

The reciprocal of a and b are 1/a, 1/b

So, the required average = (1/a + 1/b)/ 2

= (a+b)/2ab

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Q6.  If 7 is added to both the numerator and the denominator of a fraction then the fraction becomes 3/4. If 5 is subtracted from both of them then the fraction becomes 2/3. Find the sum of the numerator and denominator.

a) 70

b) 39

c) 60

d) 41

Answer key: a

Solution:

Let the fraction be x/y so, (x + 7)/ (y + 7) = 3/4                     ….. (1)

And, (x – 5)/ (y – 5) = 2/3                                                             ….. (2)

Solving we get, x = 29 and y = 41.

So x + y = 70.

We hope this post helped you understand the different types of decimal and fraction questions for RRB NTPC. For more such practice questions, register at Oliveboard.

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