Daily Practice - Higher Plus

A bag holds 6 red and n blue counters. The probability of taking a red is 3/7. Work out n.

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

A block has mass 400 g (to the nearest 10 g) and volume 24 cm³ (to the nearest cm³). Work out the upper bound of its density, to 2 decimal places.A block has mass 400 g (to the nearest 10 g) and volume 24 cm^3 (to the nearest cm^3). Work out the upper bound of its density, to 2 decimal places.

Simplify (x² - 5x - 14)/(x - 7).Simplify (x^2 - 5x - 14)/(x - 7).

y is directly proportional to √x. When x = 16, y = 32. Work out y when x = 25.y is directly proportional to sqrt(x). When x = 16, y = 32. Work out y when x = 25.