2n years ago, the age of Raju was four times that of his son and n years ago, the age of Raju was thrice that of his son. If n years later, the sum of the ages of Raju and his son will be 80 years, then the difference in the ages of Raju and his son is20 years.40 years.24 years.30 years.
Question
2n years ago, the age of Raju was four times that of his son and n years ago, the age of Raju was thrice that of his son. If n years later, the sum of the ages of Raju and his son will be 80 years, then the difference in the ages of Raju and his son is20 years.40 years.24 years.30 years.
Solution
Let's denote the current age of Raju as R and the current age of his son as S.
From the problem, we have the following equations:
-
2n years ago, Raju was four times the age of his son. This gives us the equation: R - 2n = 4*(S - 2n).
-
n years ago, Raju was thrice the age of his son. This gives us the equation: R - n = 3*(S - n).
-
n years later, the sum of their ages will be 80. This gives us the equation: R + n + S + n = 80.
-
The difference in their ages is unknown. This gives us the equation: R - S = D, where D is the difference we are trying to find.
We now have a system of four equations with four unknowns (R, S, n, D). We can solve this system to find the values of the unknowns.
Let's start by simplifying the first two equations:
- R - 4S = -6n
- R - 3S = -2n
Subtract the second equation from the first to get: -S = -4n, or S = 4n.
Substitute S = 4n into the third equation to get: R + 2n + 4n + n = 80, or R + 7n = 80.
Substitute S = 4n into the fourth equation to get: R - 4n = D.
We now have two equations with two unknowns (R and n):
- R + 7n = 80
- R - 4n = D
Subtract the second equation from the first to get: 11n = 80 - D, or n = (80 - D) / 11.
Substitute n = (80 - D) / 11 into the second equation to get: R = D + 4*(80 - D) / 11.
We now have a single equation with a single unknown (D). We can solve this equation to find the value of D.
Unfortunately, without numerical options for D, we cannot proceed further. If you provide numerical options for D, we can solve the equation to find the correct answer.
Similar Questions
How old will be the Raju if ratio of his age and one of his twin grandsons’ is 11:2 and average age of his and his both grandsons is 50 years?72 years110 years75 years150 years
he total of the ages of Jiya, Kunal and Sagar is93 years. Ten years ago, the ratio of their ages was2 : 3 : 4. What is the present age of Sagar?
answerAge of the father is twice that of the elder son. Ten years hence the age of the father will be three times that of the younger son. If the difference of the ages of the two sons is 15 years, the age (in years) of the father is?Options50605570
Rohan was 4 times as old as his son 6 years ago.After 6 years Rohan will be twice as old as his son.What is son's present age?10 years12 years14 years18 years
After five years the age of a father will be thrice the age of his son whereas five years ago, he was seven times old as his son was.What is father's present age?30 years40 years50 yearsNone of these
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.