There is a bag with only red marbles and blue marbles. The probability of randomly choosing a red marble is 3/7
There are 12 red marbles in the bag and each is equally likely to be chosen.
Work out how many marbles in total there must be.

Two sides of a triangle mesure 20cm and 30cm. what is the measure of the third side

Sarah took the advertising department from her company on a round trip to meet with a potential client. including sarah a total of 11 people took the trip. she was able to purchase coach tickets for $280 and first class tickets for $1280. she used her total budget for airfare for the trip, which was $6080. how many first class tickets did she buy? how many coach tickets did she buy?

Solving algebraic equations 2m+3=11