Question 644094
    The sum of three numbers is thirty. The second number is twice the first number, and the third number is 5 less than the second number. Find the three numbers.
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Let x = first number
then from "The second number is twice the first number"
2x = second number
and from "third number is 5 less than the second number"
2x-5 = third number
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we get our equation from "sum of three numbers is thirty"
x + 2x + 2x-5 = 30
5x-5 = 30
5x = 35
x = 7 (first number)
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second number:
2x = 2(7) = 14
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third number:
2x-5 = 2(7)-5 = 14-5 = 9