Aruna cut a cake into two halves and cuts one half into smaller pieces of equal size. Each of the small pieces is twenty grams in weight. If she has seven pieces of the cake in all with her, how heavy was the original cake ?

Answer: Option B

Explanation:

Suppose boy got x sums right and 2x sums wrong,
then,
x+2x = 48
=> 3x = 48
=> x = 16

Answer: Option B

Explanation:

Generally we may commit mistake of dividing 1200/15.
But out of 16 persons there is one captain.
so, it will be 1200/16 = 75

Answer: Option D

Explanation:

Let the number of keepers be x.
Then, total number of feet = 2*50+4*45+4*8+2x
= 2x + 312

Total number of heads = 50+45+8+x = 103 + x
Now, (2x+312) = (103+x)+224
=> x = 15

Answer: Option D

Explanation:

Let number of horses = number of men = x.

Then, number of legs = 4x + 2 x (x/2) = 5x.

So, 5X = 70 or x = 14.

Answer: Option D

Explanation:

If we read given question carefully, we get,
B+8 = C ---(i)
A-8 = C-3 ---(ii)
A+6 = 2D ---(iii)
B+D = 50 ---(iv)

Putting C = A -5 from (ii) into (i), we have :
B+8 = A-5 or A-B = 13 ---(v)

Putting D = 50-B from (iv) and (iii), we have :

A+6 = 100-2B or A+2B = 94 ---(vi)

Solving (v) and (vi), we get
B = 27 and A = 40