I agree with the OA..... MUST BE true is used here to denote that the option selected must be true for all possible values of x that can be derived from the given equation. Hence, if we choose A, there are values of x, such that -1 < x < 0, that are not satisfied by option A. Hence, option A would n...

i guess i know the answer mathematically....

each of these events are exclusive, and the outcome of one doesn't affect the outcome of another.....However, i am not yet convinced about this....

Thanks Stuart, you are correct.

However, what is the reason that in this scenario, you cannot think of them as 4 exclusive events, and say that if he takes 4 shots at the target, he will hit it atleast once?

Now that i write this, i realize why this difference is occurring. each of the points is being taken as unique. Hence, points ABCD could be interchanged by points DABC, and that is being counted as a separate rectangle. However, shouldn't this hold true? would rectangle ABCD be the same as DABC, bec...

No. of rectangles

The coordinates (x,y) of each corners of rectangle ABCD are such that x and are integers and satisfy the equations 1 < x < 6 and -3 < y < -3. The edges of the rectangle are parallel to the X and Y axes. How many distinct rectangles could be formed which would satisfy these requirements?

Thanks.

I had thought about the same point, but then went ahead with it, thinking that there wasnt a time factor involved.

Thanks again.

I applied weighted averages,

[25(10) + 40(50)]/(10+50) = 37.5

what am i doing wrong?