Question

Two numbers are respectively 25/2 % and 25% more than a third number.The first number as a percentage of the second number is? Select one: a. 60 b. 75 c. 90 d. 50

Answer 1

Answer:

Option (c), 90% is correct.

Solution:

Let, the third number is p

Step 1.

If A (say) be the first number, then A is 25/2 % more than p

Then A = p (1 + 25/2 %)

or, A = p (1 + 25/200)

or, A = p (1 + 1/8)

or, A = 9p/8 ..... (i)

Step 2.

If B be the second number, then B is 25 % more than p

Then B = p (1 + 25 %)

or, B = p (1 + 25/100)

or, B = p (1 + 1/4)

or, B = 5p/4 ..... (ii)

Step 3.

Dividing (i) by (ii), we get

A / B = 9/8 * 4/5

or, A / B = 9 / 10

or, A = B * 9/10

or, A = B * 9/10 * 100 %

or, A = B * 90%

∴ the first number is 90% of the second number.