SOLUTION: The sum of the digit of the two numbers is 5.if 10 times the tens digit is added to 4 times the unit digit,the number obtained is in the reverse order of the digit of the original

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Question 1082714: The sum of the digit of the two numbers is 5.if 10 times the tens digit is added to 4 times the unit digit,the number obtained is in the reverse order of the digit of the original number.find the number?
Found 2 solutions by josgarithmetic, ikleyn:
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
The number, 10t+u;
t, the tens place digit
u, the ones place digit

system%28t%2Bu=5%2C10t%2B4u=t%2B10u%29


The number: 23

Answer by ikleyn(52787) About Me  (Show Source):
You can put this solution on YOUR website!
.
The sum of the highlight%28cross%28digit%29%29 digits of the two highlight%28digit%29 highlight%28cross%28numbers%29%29 number is 5.
If 10 times the tens digit is added to 4 times the unit digit,
the number obtained is in the reverse order of the highlight%28cross%28digit%29%29 digits of the original number. find the number?
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The equations are 

t + u = 5,          (1)    (where t is the "tens" digit, u is the "units" digit.)
10t+4u = 10u + t.   (2)

Simplify:

t + u = 5,
9t = 6u.

t = 5-u,
9*(5-u) = 6u,

45 - 9u = 6u,

45 = 15u  --->  u = 3,  t = 2.

The original number is 23.