Answer:
Raju = 17 years
Raju's father age = 46 years
Raju's grandfather age = 72 years
Raju's grandmother = 68 years
His sister = 10 years old
Step-by-step explanation:
Raju’s father is 26 years younger than Raju’s grandfather and 29 years older than Raju. The sum of the ages of all the three is 135 years. Also, Raju's Grandmother is four times of Raju’s age and his sister is 7 years younger than him.
Let
Raju's age = x
Raju's father age = x + 29
Raju's grandfather age = (x + 29) + 26
Total ages = 135
(x) + (x + 29) + (x + 29) + 26 = 135
x + x + 29 + x + 29 + 26 = 135
3x + 84 = 135
3x = 135 - 84
3x = 51
x = 51 /3
x = 17
Raju's age = x = 17 years
Raju's grandmother = 4 times raju's age
= 4 × 17 years
= 68 years
his sister = 7 years younger than him.
= 17 - 7
= 10 years old
Raju's father age = x + 29
= 17 + 29
= 46 years
Raju's grandfather age = (x + 29) + 26
= 46 + 26
= 72 years