There is a bag with only red marbles and blue marbles. The probability of randomly choosing a red marble is 11/12. There are 84 marbles in total in the bag and each is equally likely to be chosen. Work out how many red marbles there must be.

Wait is the question correct how is choosing a marble equally likely

Look, when you want to do something like put it like x^2. x2 could mean x² or x₂. so to clear confusion, know the notation. to find the product multiply the x's and you get -8x and the y's and you get 6y. since it's all being multiplied it is just -8x6y, or answer a. although the better answer is -48xy(combining -8 and 6) because you should multiply constants whenever you can.