Harry Styles’ sandcastle is 150cm tall but the wind is blowing away sand at a rate of 5cm per minute. Cardi B’s sandcastle is 130cm tall and she it adding sand to it at a rate of 3cm per minute. After how many minutes will their sandcastles be the same height?

Ateacher noticed 5/8 of the students were wearing either blue shorts or white shorts. write two different ways this could be done.

Prove that the value of the expression 7^8–7^7+7^6 is divisible by 43.

There are three bags: a (contains 2 white and 4 red balls), b (8 white, 4 red) and c (1 white 3 red). you select one ball at random from each bag, observe that exactly two are white, but forget which ball came from which bag. what is the probability that you selected a white ball from bag a?