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The sum of a two digit number and the number obtained by reversing its digits is 121. Find the number if its units place digit is greater than the tens place digit by 7. |
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Answer» Suppose, the units place digit of the two digit number is y and the tens place digit is x ∴ the number is 10x + y ∴ the number obtained by reversing the digits is 10y + x ∴ from the given conditions, (10x +y) + (10y + x) = 121 ∴ 11x + 11y = 121 ∴ x + y = 11 .......... (I) Also, x = y + 7 ∴ x - y = 7 ..........(II) ∴ Adding (I) and (II), 2x = 18 x = 9 ∴ from (I) a + y = 11 y = 2 ∴ the two digit number is 29. |
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