SOLUTION: A two-digit number is 4 times the sum of its digits. The tens digit is 3 less than the units digit. What is the number?

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Question 602440: A two-digit number is 4 times the sum of its digits. The tens digit is 3 less than the units digit. What is the number?
Found 2 solutions by lwsshak3, ewatrrr:
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
A two-digit number is 4 times the sum of its digits. The tens digit is 3 less than the units digit. What is the number?
**
let u=units digit
t=tens digit
..
t=u-3
10t+u=4(t+u)
10t+u=4t+4u
6t=3u
6(u-3)=3u
6u-18=3u
3u=18
u=6
t=6-3=3
number: 36

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

A two-digit number is 4 times the sum of its digits. The tens digit is 3 less than the units digit. 

Let x and (x-3) represent the units digit and tens digit respectively

Question states***

10(x-3) + x = 4[(x-3) + x] 

Solving for x

  11x - 30 = 8x - 12

     3x = 18

      x = 6, the units digit, the tens digit (x-3) is 3

the number is 36

CHECKING our Answer***

36 = 4*9 = 36