Question 773626: the number has 3 digits
the number is less than 140
the number has 7 as a factor
the number is even
the sum of the digits is less than 9
Answer by solver91311(24713)   (Show Source):
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140 divided by 7 is 20, so since the desired number is LESS than 140, and 7 is a factor, the other factor must be less than 20.
7 times 14 is 98, so the other factor has to be greater than 14. So far we have narrowed it down to 7 times 15, or 16, or 17, or 18, or 19.
But the desired number is even, that means if 7 (an odd number) is a factor, the other factor must be even. So we eliminate the odd posibilities above, namely 15, 17, and 19.
The sum of the digits of 16 is 7 and the sum of the digits of 18 is 9. Only one is LESS than 9.
I'll let you take it from here.
John
Egw to Beta kai to Sigma
My calculator said it, I believe it, that settles it
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