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07252007  #1 
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Algebra Tease. The answer is 25 so show me the work please :)?
The sum of the digits of a two digit number is 7. When the digits are reversed, the number is increased by 27. Find the number

07252007  #2 
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Let digits at tens place is xand at units place is yso no is 10x+yx+y=7.....1stBy reversing the digits, number becomes 10y+xSo10x+y =10y+x 279y9x=27yx = 3....2ndsolving both we get2y=10y=5so x = 2so the no is 25.

07252007  #3 
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25522+5 = 75225=27

07252007  #4 
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Let a be the first digit and b be the second digit.a+b=710a+b(10b+a)=27Solving,a+b=79b9a=2718b =90 =>b=5a=2So, the number is 25.

07252007  #5 
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Let x = 1st digit; y = 2nd digit.1st equation:x + y = 7x = 7  y2nd equation10y + x)  (10x + y) = 2710y + x  10x  y = 279x = 27  9yx = 3 + y3rd equation (pair off the value of x in 1st & 2nd equations to arrive at y, the 2nd digit):7  y =  3 + y10 = 2y5 = y7  5 = x2 = xAnswer:1st digit is x or 2; 2nd digit is y or 5.

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