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- The difference of the digits of a 2-digit number is 3. If the digits are interchanged and thenew number is added to the original number, the result is 77. Find the original number. |
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Answer» Answer: 52 or 25 Step-by-step explanation: let the digits of two digit number be x and y so, number will be 10x + y given that ,The DIFFERENCE of the digits = 3 so, x - y = 3 .....(1) and also given that If the digits are interchanged (means 10x + y to 10y + x) then new number is ADDED to the ORIGINAL number, the result is 77 original number is 10x + y number formed by interchanging of digits = 10y + x ATQ, 10x + y + 10y + x = 77 11x + 11y = 77 x + y = 77/11 x + y = 7 .....(2) now from eqn (1) and (2) by adding both x - y + x + y = 3 + 7 2x = 10 x = 10/2 x = 5 putting the value of x on (1) x - y = 3 5 - y = 3 -y = 3 - 5 -y = -2 y = 2 x = 5 original number = 10x + y = 10(5) + 2 50 + 2 52 so, original number = 52 or 25hope it helps |
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