90 is what percent greater than a number which is 5 times greater than

This is a question where we have to take one calculation at a time, lest we mix up the order.

Let's start with the simplest: 30% of 40 = 12.

A number that is 5 times greater than 12 = 6 times of 12 = 72.

Therefore, the question now turns to “90 is what percent greater than 72?”
This is an easy question to solve now.

Percentage difference = \(\frac{(90 – 72) }{ 72 }\)* 100 = ¼ * 100 = 25%.

The correct answer option is B.

Hope that helps!
Aravind B T

The hidden words.
5 times of x = 5x
5 times greater than x = x + 5x

Posted from my mobile device

Hello Dinakarajay,

This is a very common mistake that test takers make in percentages questions.

You have to understand that words like ‘Of’, ‘greater than’, ‘lesser than’ are very important in these questions. Whatever comes after these words represents the whole; the whole is the reference value.

For example, 15 is what percent of 60? We are trying to find out 15 is what part of the whole, which is 60.

Now, if the question is “120 is what percent OF 40?”, we would answer the question with 300%. Or in other words, we would say 120 is 3 times OF 40.

On the other hand, if the question was “120 is what percent more than 40?”, the answer would be 200%. You are now excluding the WHOLE (i.e. 40) because you are only trying to find the increment compared to the whole.

Using the same concept, 5 times greater than 12 = 5 times of the whole (12) added to the whole (12) = 6 times of the whole.

Easy way to remember: If B is 'n' times of A, B is "(n-1) * 100%" more than A.

Hope that helps!
Aravind BT

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