SOLUTION: find the largest two-digit number which is equal to four times the sum of it's digits

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Question 124624: find the largest two-digit number which is equal to four times the sum of it's digits
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
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find the largest two-digit number which is equal to four times the sum of it's digits
:
We can find the relationship between the two digits with an equation:
10x + y = 4(x+y)
10x + y = 4x + 4y
10x - 4x = 4y - y
6x = 3y
2x = y; divided equation by 3
:
We can see that x cannot = more than 4, if y is a single digit, therefore
x = 4, y = 8; Largest 2 digit number is 48, that satisfied the problem