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the sum of the digits of a two digit number is 15 the number obtained by interchanging the digits exceeds the given number by 1 the number is |
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Answer» Let the number be 10x+ywith digits x,ytherefore x+y=15........(i)again, 10y+x-10x-y=9or, 9y-9x=9or, x-y=-1..........(ii)solving equation (i) and (ii) we getx+y=15........(i)x-y=-1..........(ii)------------------------2x=14x=7andy=8therefore the number is 10x+y=10x7+8=78 78 is the desired number |
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