Question 930482
x = second number
x/2 = first number {first number is half the second}
3x = third number {third number is three times the second}


x + x/2 + 3x = 81 {the sum of the three numbers is 81}
2x + x + 6x = 162 {multiplied entire equation by 2 to eliminate fraction}
9x = 162 {combined like terms}
x = 18 {divided each side by 9}
x/2 = 9 {substituted 18, in for x, into x/2}


the first number is 9
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