Q. 16 - if the squared value is postiive and odd, it means:
1) XY (product of x and y) is odd
a) that means that X and Y are also odd (as the product of 2
odd number is odd, else its even, if one of the numbers is
even)
b) if both X and Y are odd their sum is even
2) XY (product of A and y) could be +ve or -ve, as the square of a value is always positive, we cannot be sure if the product was -ve or +ve.
From the above, Option "e" will be a fit
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q. 17 Without going too much into the calculations, only option B has both dimensions as more than 20. If we are wrapping on the smaller sides, we will need atleast, 8+2+8+2 = 20 or more and the other side is already 20, so this alone gives us sufficient information that option "b" will be a fit.
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Q. 18 - When divied by the same number, the sum of 2 numbers will give the remainder which will be equal to the sum of individual remainders. Based on this, any of the answer choises when divided by 6 doesnt leave a remainder of 4 is the answer to this question. In the case of this question, option A - 86, leaves a remainder of 2 and all others leave 4 as remainder.
So option "a" will be a fit.
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