# Maths question – common difference, 204 red and green apples

Maths tip: One more example of "common difference". By now, these type of questions shouldn’t be a problem

Maths tip: One more example of "common difference". By now, these type of questions shouldn’t be a problem

Maths tip: Here’s another example of "common difference".

Maths tip: Another type of problem sums involve before-after scenarios, where the difference between two quantities remain unchanged. An example is shown in the picture. Recognising the question is half the battle won. Typically the question tells you a ratio of the "before" scenario. After an equal amount is removed / added / after a[…]

Maths tip: Michelle had four times as many stickers as Vanessa. After each of them bought an equal number of stickers from the bookshop, Michelle had thrice as many stickers as Vanessa. If Vanessa had 57 stickers in the end how many stickers did each of them buy from the bookshop?