Daily Practice - Higher Plus

A block has mass 210 g (to the nearest 10 g) and volume 5 cm³ (to the nearest cm³). Work out the upper bound of its density, to 2 decimal places.A block has mass 210 g (to the nearest 10 g) and volume 5 cm^3 (to the nearest cm^3). Work out the upper bound of its density, to 2 decimal places.

Solve x² + y² = 225 and y = x + 3 simultaneously.Solve x^2 + y^2 = 225 and y = x + 3 simultaneously.

y is inversely proportional to x². When x = 5, y = 18. Work out y when x = 3.y is inversely proportional to x^2. When x = 5, y = 18. Work out y when x = 3.

A triangle has sides of 9 cm and 12 cm and an area of 38.18 cm². Work out the acute angle between those two sides, to the nearest degree.A triangle has sides of 9 cm and 12 cm and an area of 38.18 cm^2. Work out the acute angle between those two sides, to the nearest degree.

A bag holds 7 counters, r of them red. Two are taken without replacement and P(both red) = 1/21. Work out r.