Question 430382
"Ruby is three years older than Sam. Sum of their age is 33. How old are both of them?"


x = Sam's age now
x + 3 = Ruby's age now


x + x + 3 = 33 {sum of their ages is 33}
2x + 3 = 33 {combined like terms}
2x = 30 {subtracted 3 from both sides}
x = 15 {divided both sides by 2}
x + 3 = 18 {substituted 15, in for x, into x + 3}


Sam is 15 and Ruby is 18
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