SOLUTION: I have a word problem that I need some help with. The sum of the digits of a three-digit number is 15. The tens place digit is twice the hundreds-place digit, and the ones

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Question 153718: I have a word problem that I need some help with.
The sum of the digits of a three-digit number is 15. The tens place digit is twice the hundreds-place digit, and the ones place digit is 1 less than the hundreds-place digit. Find the three digit number.
I thought
15=2x+x+x-1
Im pretty sure this isn't right. could you please help me with this word problem. when do I know to use x or y? please help me work through the equation also.
thank you
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
The sum of the digits of a three-digit number is 15. The tens place digit is twice the hundreds-place digit, and the ones place digit is 1 less than the hundreds-place digit. Find the three digit number.
.
Let x = hundreds-place digit
then
2x = tens-place digit
x-1 = ones-place digit
.
x + 2x + (x-1) = 15
4x - 1 = 15
4x = 16
x = 4 (hundreds-place digit)
2x = 8 (tens-place digit)
x-1 = 3 (ones-place digit)
.
Therefore you 3 digit number is:
483