Gcse Maths: How to decipher between the different types of percentage questions?

Currently we've learnt that there are 6 different types of percentage questions in gcse maths and we're learning the methods to answer them. However, since these questions are written as word problems, it's hard for me to tell what method I should use to answer because I can't tell what type of question it is.


For example within reverse percentages alone there are 2 different types of questions. One type is "x is 10% of the money you have in a wallet how much money is in the wallet", and the other type being "you have £10 in your wallet. You find money on the floor and put it in your wallet, the amount increases by 25%. How much do you have now". My teacher taught us one method to solve both these types of answers, but the method only gives the correct answer for one of those questions so obviously one of them is not like the other.


Anyway, my general question is if anyone has struggled with percentages for this reason, and if do, how do you make it easier?

Will you be allowed to use a calculator with these sorts of questions in the exam?

Will you be allowed to use a calculator with these sorts of questions in the exam?

think of the percentage as a decimal of the original value, i.e 10% is 0.10; 25% is 0.25; 173% is 1.73, etc. So for example (in the form of one of your examples)
Q. I have found £4 on the floor, i put it in my wallet. The original amount of money in my wallet has now increased by 25%.
What was the original amount of money?

A. £ 4 = 25% of original amount

So by dividing the £4 by 25, we can find what 1% of the original value was.
£4 ➗ 25 = £0.16

So we now know that 1% of the original value is £0.16
Now to find the the full original value you just need to find multiply the 1% value by 100 to find 100% of the original value.

1% = £0.16
So, £0.16 x 100= £16


Final Answer: Original value = £16

The method I was taught is:

New amount ➗ multiplier = original amount

But where I get confused there is that if the percentage was 4% for example:

If it increases by 4% the multiplier is 1.04
If it decreases by 4% the multiplier is 0.96
If its not increasing or decreasing, and we are just trying to find a total with a percentage as part of the value the multiplier is just the decimal form of the percentage (0.4).

Now my trouble is that when reading the question, I don't know which if those multipliers to use. Should I just disregard my method and use yours, will it work for all reverse percentage questions? Because my method does not.

No, I would definitely recommend doing what your teacher has taught you, however there must be a misunderstanding with their method so you should just show your teacher what part you don’t understand and ask them to explain.

If you want you can give me an example of a question you don’t know how to do and I will explain how you would go about solving it.