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  • 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

Someone please answer this question, I'm not able to figure out the solution. Please solve this problem.

Thanks & Cheers, Pradeep Kumar.M

J. W. Tanner
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pradeep kumar
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    Welcome! What have you tried to solve this problem? You should show your efforts or explain where you get stucked! – Bargabbiati Dec 15 '20 at 15:11
  • Hi Bargabbiati, I have tried to solve this problem by using algebra equations, but unfortunately that didn't materialized. This is my work which i have tried. F = 4s s = F / 4 F + s = 120 F/4 + F = 120 – pradeep kumar Dec 15 '20 at 15:13
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    A system of 3 equation with the 3 unknown ages. – Mauro ALLEGRANZA Dec 15 '20 at 15:14
  • @MauroALLEGRANZA 3 equations and 4 unknown, but integer solutions only (A Diophantine equation at the end if I am not wrong) – Damien Dec 15 '20 at 15:22
  • @pradeepkumar You should (always!) include your attempts in your post. Otherwise it looks like you didn;t put in any effort, and on this site we like to see that effort. So, put this work in your post, or else you're going to keep getting downvotes and close votes. – Bram28 Dec 15 '20 at 15:25
  • $s+4s+(2\cdot4s-10)=120$, I don't think we'll have to revive Ramanujan for that. –  Dec 15 '20 at 15:25
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    @Damien - why four ? The man age, its son age, its father age. – Mauro ALLEGRANZA Dec 15 '20 at 15:35
  • @MauroALLEGRANZA Sorry, I read the " at the wrong place. In my understanding, the narrator was not the man. So "my age" was an additional parameter. And this more complex problem has an unique solution, thanks to the integer constraint ... – Damien Dec 15 '20 at 15:39
  • https://math.stackexchange.com/q/647035/832559 see this problem. – random Dec 15 '20 at 15:50

1 Answers1

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Let x = the man's age

x/4 = the man's son's age

2x - 10 = the man's father's age

x/4 + 2x - 10 + x = 120

x/4 + 3x = 130

13x = 520

x = 40

thus, the age of the man is 40

Erine Solera
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