Daily Practice - Higher Plus

A bag holds 3 red, 3 blue and 6 green counters. Two are taken without replacement. Given neither is green, what is the probability both are red?

A histogram has four 20-wide classes from 0, with frequency densities 0.5, 2, 3, 1. Which class contains the median?

A block has mass 390 g (to the nearest 10 g) and volume 21 cm³ (to the nearest cm³). Work out the upper bound of its density, to 2 decimal places.A block has mass 390 g (to the nearest 10 g) and volume 21 cm^3 (to the nearest cm^3). Work out the upper bound of its density, to 2 decimal places.

In an algebraic proof, how would you write a multiple of 5 in terms of an integer n?

y is directly proportional to x. When x = 25, y = 40. Work out y when x = 81.y is directly proportional to sqrt(x). When x = 25, y = 40. Work out y when x = 81.