How old is James now?

James’ dad is 5 times older than James, and James is twice as old as his sister Sara. In two years, the sum of their ages will be 58. How old is James now?

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Age now
x = Jame's age now
5x = James' dad's age now  {James' dad is 5 times older than James}
x/2 = James' sister, Sara's age now  {James is twice as old as his sister}

Age in 2 years
x + 2 = James in 2 years  {added 2 onto current age}
5x + 2 = James' dad in 2 years {added 2 onto current age}
x/2 + 2 = Sara's age now  {added 2 onto current age}

(x + 2) + (5x + 2) + (x/2 + 2) = 58  {added ages together, and set equal to 58}
x + 2 + 5x + 2 + x/2 + 2 = 58  {removed parentheses}
6x + x/2 + 6 = 58  {combined x with 5x and added the 2's}
6x + x/2 = 52  {subtracted 6 from each side}
12x + x = 104  {multiplied entire equation by 2, to eliminate fraction}
13x = 104  {combined like terms}
x = 8  {divided each side by 13}

James is 8 now

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