SOLUTION: the sum of three numbers is 81. the first number is half the second, and the third number is three times the second one. what is the value of the first number?
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Question 930482: the sum of three numbers is 81. the first number is half the second, and the third number is three times the second one. what is the value of the first number?
Answer by algebrahouse.com(1659) (Show Source): You can put this solution on YOUR website!
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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