Higher Plus

A bag holds 6 red, 6 blue and 5 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, 1, 3. Which class contains the median?

A block has mass 650 g (to the nearest 10 g) and volume 20 cm³ (to the nearest cm³). Work out the upper bound of its density, to 2 decimal places.A block has mass 650 g (to the nearest 10 g) and volume 20 cm^3 (to the nearest cm^3). Work out the upper bound of its density, to 2 decimal places.

The point (-5, 0) lies on y = f(x). Write down its image on y = -f(x).

y is directly proportional to x. When x = 49, y = 21. Work out y when x = 81.y is directly proportional to sqrt(x). When x = 49, y = 21. Work out y when x = 81.