Question

If 10^ y =121 then 10^y/2+1
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Answer 1

Step-by-step explanation:

Let the tens digit of the number be x and the units digit be y.

So, the number is 10x + y.

The number obtained by interchanging the digits will be 10y + x.

According to question, we have

10x + y + 10y + x = 121

⇒ 11x + 11y = 121

⇒ 11( x + y ) = 121

⇒ x + y = 11 ...(1)

And,

x - y = 3 ...(2)

Adding (1) and (2), We get

∴ 2x = 14

x = 7

∴ y = 11 - x = 11 - 7 = 4

Hence, the number is 74.