Out-of-the-box methods for a few Mock-7 questions

Q=51- If you look at the answer options, you will understand the way in which the calculations were done to arrive at the answer. Basically, the two arc areas have been subtracted from something. They will add up to a semicircle with radius 5. Thus the amount to be subtracted is 1/2(pi*r^2) i.e. 12.5*pi. So, only options (1) and (5) can be correct. Now, if you just approximate the upper half of the figure as a rectangle of 10*6=60, and lower half as 10*5=50. you know that your first part must be about 110. The first option evaluates to approx. 95-12.5*pi, whereas the fifth option is only 60-12.5*pi. Hence correct ans is (1).

Q-53-In this question we have to find the perimeter, so I can say perimeter of trapezium ABDE is ab+bd+de+ae out of which we know the length of de=4, ae=8 so ae+de=12 and it is given that db=bc so I can say ae+de+ab+bc which implies 12+ac. Can I say that only the ans option 5 is written in the same form (integral part must be at least 12)?

Q-62-In this question the position of a circle is not defined so surely two cases are possible that means the option should contain combination which is not given in any option that means the ans has to be "cannot be determined".

Q-72 In this question polynomial is of the form (x-1)(x-2)(x-3)......................(x-51)+x, then only you will get the given remainders. When you put x=52, you will get f(52)=51!+52 and f(0)=-51! therefore the value of f(52)+f(0)=51!+52-51!=52.

So all you CAT aspirants, according to me the quant section was manageble and not difficult and the only thing you need to focus on is to be smarter than intelligent. While analyzing, the ideology is to identify where you went wrong and, yes-the important thing is if you got the right answer. Still look at the key and check what method they have used. It will definitely give you a new dimension to approach the question.