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Pradeepkaslp

Guest

A man said "I am only four times my son's age

A man said "I am only four times my son's age. My father is 10 years less than twice my age.
And together we form age of 120 years old”. Find out age of the man

Bob

Administrator

Registered: 2010-06-20

Posts: 10,640

Re: A man said "I am only four times my son's age

hi Pradeepkaslp

Welcome to the forum.

The way I was taught to do these is to let one of the unknowns be x.

Let's say the son is x.

Then the man, (the father) is 4x.

And the grandfather is double that less 10 so 8x - 10

Together the ages add up to 120 so

x + 4x + 8x - 10 = 120

I'll leave you to finish off from there.

Bob

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Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob

happy snow

Member

Registered: 2021-03-17

Posts: 1

Re: A man said "I am only four times my son's age

the son's age is: (120+10) ÷ (1+4+8) = 10
the father is 10 × 4 =40
the grandpa is 2×40 -10 =70

check: 10+40+70=120

Jai Ganesh

Administrator

Registered: 2005-06-28

Posts: 48,837

Re: A man said "I am only four times my son's age

Hi happy snow,

Welcome the the forum!

The solution, son's age is 10 years old, therefore, the father's are is 40 years old, is right!

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