Question 930499
x = second number
x/2 = first number
3x = third number


x + x/2 + 3x = 72 {sum of the three numbers is 72}
2x + x + 6x = 144 {multiplied entire equation by 2 to eliminate fractions}
8x = 144 {combined like terms}
x = 18 {divided each side by 8}
x/2 = 9 {substituted 18, in for x, into x/2}


9 is the first number
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