No matter whether it’s RBI Grade B exam or IBPS PO exam, age problems are quite crucial in any banking or government examination. The main element of age problems is the factor for students to be able to convert the statements regarding the ages into equations. There could be various kinds of questions on this topic, but they are all related to each other in some way. In this blog post, we shall discuss the two kinds of age questions for bank exams that have been asked multiple times in the past years’ question papers and have a good chance of being asked again.
Age problems – Type 1 Question
The first kind of age problems is the simplest kind. In this case, the ratio will be provided in the question and the question requires the computation of ages. To understand the same, consider the following example:
The ages of person A and person B are in the ratio 4:5. After 5 years, their ages will be in the ratio of 7:9. Compute their present ages.
Let the ages of Person A and Person B be ‘x’ years and ‘y’ years. So, currently it is given that:
x / y = 4 / 5
Or, by cross-multiplication: 5x = 4y
Or, 5x – 4y = 0 —- equation (i)
Now, in the second statement, it is said that after 5 years, they will be in the ratio of 7:9, which means:
Person A’s age after 5 years = (x + 5) years
Person B’s age after 5 years = (y + 5) years
And it’s also given that, (x + 5) / (y + 5) = 7 / 9
Or, 9*(x + 5) = 7*(y + 5) = 9x + 45 = 7y + 35
Or, 9x – 7y = 35 – 45
Or, 9x – 7y = -10 —- equation (ii)
Now, we can solve equation (i) and equation (ii). Therefore, we can do so by method of elimination.
- 5x – 4y = 0 [Multiply equation by 7]
- 9x – 7y = -10 [Multiply equation by 4]
This gives us, -x = 40 years, or simply x = 40 years (because age cannot be negative).
When we substitute the value of x = 40 in equation (i), we get: 5(40) – 4y = 0: 200 – 4y = 0: 200/4 = 50 = y
Therefore, the present ages of x and y are 40 and 50 years respectively.
Age problems – Type 2 Question
The second kind of questions from the age problems in the bank examinations is the more important one because it includes the statements only and the ratios will have to be computed by the student. To better understand, check out the example below:
After 5 years, the age of Person A will be 2 times as old as that of Person B. Person C, who is the brother of Person A is 5 years younger than Person A. 5 years ago, Person A was three times as old as Person C. Find the current age of Person B.
Let the age of Person B be ‘x’ years while that of Person A would be ‘y’ years and that of Person C would be ‘z’ years.
So, after 5 years, Person A will be 2 times as old as Person B, in terms of equations that can be written as:
y + 5 = 2*(x + 5)
Or, y + 5 = 2x + 10
Or, y = 2x + 10 – 5
Or, y = 2x + 5 (equation 1)
Now, it has been said that Person C is 5 years younger than Person A, and so:
z = y – 5 (equation 2)
Also, in the question, it has been said that 5 years ago, Person A was as much as 3 times older compared to Person C. So the equations would be:
z – 5 = 3*(x – 5)
Or, z – 5 = 3x – 15
Or, z – 3x = -15 + 5
Or, z – 3x = -10
Or, z = 3x – 10 (equation 3)
When we substitute the value of ‘y’ taken from the 1st equation in the 2nd equation, we have:
y = 2x + 5 (equation 1)
z = y – 5 (equation 2), so
z = 2x + 5 -5
z = 2x (equation 4)
Now, we substitute the value of euqation 4 in equation 3, and we get:
z = 2x (equation 4)
z = 3x – 10 (equation 3)
So, 2x = 3x – 10
Or, 10 = 3x – 2x
Or, 10 = x
Therefore, the age of person B is 10 years.
So, those are the 2 main kinds of questions that you can expect in your banking examinations. If you are ready to practice, how about you start right away with the Oliveboard’s RBI Grade B 2018 Mock Test Package?
All the Best!