Measure the length of the line to the nearest tenth of a centimeter

How much dextrose 70% must be mixed with dextrose 5% to prepare 1,000 ml of dextrose 20%?

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?

Mis the midpoint of rq if rm equals 2x + 5 and mq equals 4x - 9 what is the length of rq