SOLUTION: a two digit number is 6 times its units digit. the sum of its digits is 3. Find the number. thanks for the help!

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Question 5480: a two digit number is 6 times its units digit. the sum of its digits is 3. Find the number.
thanks for the help!
Answer by Abbey(339) About Me  (Show Source):
You can put this solution on YOUR website!
Let x be the digit in the 10's column
Let y be the digit in the one's column
So in order to find the value of the number we multiply the x by 10 and add it to the y (think about the number 23... it represents the value (2*10) + 3)
The number is written as 10x+y
The sum of the two digits is 3:
x+y=3
we can rewrite this by subtracting y from both sides as:
x=3-y
the number is 6 times the unit digit:
(6y=10x+y)
substitute the 3-y in for the x value and solve for y:
6y = 10(3-y)+y
6y = 30-10y+y
6y=30-9y
15y=30
y=2
if the sum of the digits is 3, then x=1
Our number is 12
check the answer:
2+1=3 (true)
12=6*2 (true)