Let 62976/N = 123

Correct Option: C

Let 62976/N = 123
Then N = 62976 / 123 = 512.

Given Exp. = 6/7 + [(y - x)/(y + x)]
= 6/7 + [1 - (x/y) / 1 + (x/y)]

Correct Option: C

Given Exp. = 6/7 + [(y - x)/(y + x)]
= 6/7 + [1 - (x/y) / 1 + (x/y)]
= 6/7 + [1 - (3/4)] / [1 + (3/4)]
= 6/7 + 1/7 =1.

Let the number be N.
According to the question,
N - (N x 3/4) =163

Correct Option: D

Let the number be N.
According to the question,
N - (N x 3/4) =163
⇒ N/4 =163
∴ N=652

Let the positive number be N.
According to the question,
N + 10 = 200 / N

Correct Option: B

Let the positive number be N.
According to the question,
N + 10 = 200 / N
⇒ N² + 10N = 200
⇒ N² +10N - 200 =0
⇒ (N - 10)(N + 20) = 0
∴ N = 10 & N= -20
But N not equal to -20 since N is a positive number
So, the required number is 10

Total share given by the person = (1/4) + (1/2) + (1/5)

Correct Option: B

Total share given by the person = (1/4) + (1/2) + (1/5)
= (5 + 10 + 4) / 20
=19/20