The product of an integer and its successive integer is half of a number 4 more than the number fo

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02 Aug 2010 Find the integer

The product of an integer and its successive integer is half of a number 4 more than the number formed by
these two integers taken in increasing order. Sum of the two integers is equal to

OPtion

1) 15
2) 12
3) 13
4) 14
5) 11
6) 16
7) 17
8) 10
9) 9
10) 8

Solution

According to the given condition
x. (x+1) = [{10x + (x+1)}+4]/2
=> x2 +x = (11x +5)/2
=> 2x2 +2x = 11x +5
=> 2x2 -9x -5 = 0
=> x = 5, -1/2
Therefore the integers are 5 and 6
You can also check the options

Correct Option: 5 Best Solution (7)