Question3 and 4

In this page question3 and 4 we are going to see solution for third and fourth questions.

Question 3:

The ages of Abraham and Adam are in the ratio 5:7. If Abraham was 9 years older and Adam 9 years younger, the age of Abraham would have been twice of Adam. Find the present ages of them.

Solution: Let "5x" be the age of Abraham

Let "7x" be the age of Adam

If Abraham was 9 years older then his age will be 5x + 9

If Adam was 9 years younger then his age will be 7x - 9

The age of Abraham would have been twice of Adam.

5x + 9 = 2 (7x - 9)

5x + 9 = 14x - 18

5x - 14x = -18 - 9

- 9x = -27

x = 3

Present age of Abraham = 5x = 5 (3) = 15 years

Present age of Adam = 7x = 7(3) = 21 years

So the correct option is (C) 15 years , 21 years

Question 4:

Airi's mother is four times as old as Airi. After five years her mother will be  three times as old as she will be then .What is their present ages.

Solution: Let "x" be the age of Airi

Let "4x" be the age of Airi's mother

After 5 years

age of Airi = x + 5

age of her mother = 4x + 5

her mother will be three times as old as her.

So            4x + 5 = 3 (x + 5)

4x + 5 = 3x + 15

4x - 3x = 15 - 5

x = 10

Present age of Airi = 10 years

Present age of Airi's mother = 4x = 4 (10)

= 40 years

So the correct option is (A) 10 years , 40 years

Question3 and 4 to Worksheet 