Daily Practice - Higher Plus

A bag holds 7 red, 7 blue and 3 green counters. Two are taken without replacement. Given neither is green, what is the probability both are red?

A histogram has four 10-wide classes from 0, with frequency densities 0.5, 3, 2, 1. Which class contains the median?

A block has mass 480 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 480 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.

Prove that the sum of 7 consecutive integers is always a multiple of 7. State the simplified sum you would use.

y is directly proportional to √x. When x = 16, y = 36. Work out y when x = 64.y is directly proportional to sqrt(x). When x = 16, y = 36. Work out y when x = 64.