SOLUTION: find three numbers in arithmetic progression whose sum is 21 and whose product is 180?

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Question 192687: find three numbers in arithmetic progression whose sum is 21 and whose product is 180?
Answer by solver91311(24713) About Me  (Show Source):
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If the arithmetic progression has a common difference of d, and the first of the three numbers is x, then the second number must be x + d and the third, x + 2d.

So if the sum is 21, then:







is the first number,

is the second number, and

is the third number.

Now, if the product is 180, then:









Rationalizing the denominator:



and the three numbers are:

,

, and

.



John