Question

the sum of digits of a two digit number is 12. if 18 is added to the number, the digits are reversed. find the original number.
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Answer 1

Answer:

57

Step-by-step explanation:

Let, the number be 10x+y

Given, x+y=12

if 18 is added to 10x+y the digits are reversed i.e, 10y+x

10x+y+18=10y+x

10y+x-10x-y=18

9y-9x=18

y-x=2

simplify the equations y+x=12 and y-x=2

Then we get y=7

substitute y=7 in x+y =12

Then we get x=5

10x+y = 10 x 5 + 7

= 50 +7 = 57

Hence, required number is 57