Math
posted by Ant14 .
The sum of the ages of Travis, Mac and Ellie is 44. Travis is 4 years older than Ellie and Mac is twice as old as Ellie. How old is each?

let x = age of Travis
let x4 = age of Ellie (since Travis is four years older than Ellie)
let 2(x4) = age of Mac (since he is twice older than Ellie)
since the sum of their ages is 44,
x + x  4 + 2(x  4) = 44
2x  4 + 2x  8 = 44
4x  12 = 44
4x = 56
x = 14 yrs old (Travis)
x4 = 10 yrs old (Ellie)
2(x4) = 20 yrs old (Mac)
hope this helps~ :) 
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