Daily Practice - Higher Plus

A bag holds 6 counters, r of them red. Two are taken without replacement and P(both red) = 2/5. Work out r.

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

A block has mass 810 g (to the nearest 10 g) and volume 11 cm³ (to the nearest cm³). Work out the upper bound of its density, to 2 decimal places.A block has mass 810 g (to the nearest 10 g) and volume 11 cm^3 (to the nearest cm^3). Work out the upper bound of its density, to 2 decimal places.

Work out the coordinates of the turning point of y = x² + 4x + 9.Work out the coordinates of the turning point of y = x^2 + 4x + 9.

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