Question 128109: The sum of a two-digit number and its reverse is 121. The ones digit is seven more than the tens digit.what is the number? Answer by edjones(8007) (Show Source):
You can put this solution on YOUR website! Let t be the tens digit and u be the units digit.
The number = 10t+u
u=t+7
10t+(t+7)+10(t+7)+t=121
10t+t+7+10t+70+t=121
22t+77=121
22t+77-77=121-77
22t=44
t=2
u=2+7=9
29 is the number.
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Check:
29+92=121
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Ed