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