## General question

Forum for the GRE subject test in mathematics.
Ompack77
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Joined: Wed Apr 05, 2017 5:05 pm

### General question

The ratio of the ages of two friends Nilton and Hilton is 3:5 respectively and that of Hilton and Nicola is 3:5 respectively. Given that the sum of their ages is 147; how old is Hilton? Need a good explanation please please     zl0001
Posts: 12
Joined: Thu Jan 26, 2017 7:05 pm

### Re: General question

Ompack77 wrote:The ratio of the ages of two friends Nilton and Hilton is 3:5 respectively and that of Hilton and Nicola is 3:5 respectively. Given that the sum of their ages is 147; how old is Hilton? Need a good explanation please please     If you assume Hilton is 15x. Then you can use x to denote the other two people as well (with the ratios above). Add them up, find an equation and solve it.

verysweetjuices
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Joined: Sat Aug 27, 2016 3:47 pm

### Re: General question

Ompack77 wrote:The ratio of the ages of two friends Nilton and Hilton is 3:5 respectively and that of Hilton and Nicola is 3:5 respectively. Given that the sum of their ages is 147; how old is Hilton? Need a good explanation please please     Nilton to Hilton is 3:5.

Hilton to Nicola is also 3:5.

And we are told that Nilton + Hilton + Nicola = 147.

Assume Nilton's age is X.

If Nilton is X, what is Hilton's age? It means that X/Hilton = 3/5, or that Hilton = 5X/3.

Now, we have two ages: X, 5X/3.

What is Nicola's age?

Well, Hilton / Nicola = 3/5. But if Hilton = 5X/3, we know that (5X/3)/Nicola = 3/5, or Nicola = 25X/9.

Now we have all the ages in terms of X, which is Nilton's age.

X + 5X/3 + 25X/9 = 147. Now, just solve for X.