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Question 944200: A two digit number is four times the sum of the digits. How many number satisfy the condition?
Answer by ankor@dixie-net.com(22740)   (Show Source):
You can put this solution on YOUR website! A two digit number is four times the sum of the digits.
How many numbers satisfy the condition?
:
let a & b be the two digits
then
10a+b = the number
:
"A two digit number is four times the sum of the digits."
10a + b = 4(a + b)
10a + b = 4a + 4b
10a - 4a = 4b - b
6a = 3b
simplify, divide by 3
2a = b
We see that a can = 1,2,3 & 4, so that b is a single digit
a = 1, 12 is the number
a = 2, 24 is the number
a = 3, 36 is the number
a = 4, 48 is the number
:
4 numbers satisfy this condition
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