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How many two digit numbers are there which are more trebled their digits reversed |
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Answer» enote the digit in the tenth PLACE and y denote the digit in unit place.. So, the number may be written as x y 10 + in the expanded FORM. (just like 35= 10(3) +5) When the digits are reversed, x becomes the digit in unit place and y becomes the digit in the tenth place. The changed number, in the expanded form is 10y+x. According to the first CONDITION, we have y=2x which is written as 2x−y=0 (1)Also, by second condition, we have(10+x)−(10x+y)=27That is, −9x+9y=27→−x+y=3 (2)Adding equations (1) and (2), we GET x= 3. Substituting x 3 = in the equation (2), we get y = 6. Thus, the given number is (3×10)+6=36. |
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