Higher Plus

A histogram has two bars: one 5 units wide with frequency density 2.5, one 20 units wide with density 3.5. How many values in total?

A block has mass 310 g (to the nearest 10 g) and volume 19 cm³ (to the nearest cm³). Work out the upper bound of its density, to 2 decimal places.A block has mass 310 g (to the nearest 10 g) and volume 19 cm^3 (to the nearest cm^3). Work out the upper bound of its density, to 2 decimal places.

Solve x² + 4x - 5 < 0.Solve x^2 + 4x - 5 < 0.

y is directly proportional to x². When x = 3, y = 45. Work out the positive value of x when y = 245.y is directly proportional to x^2. When x = 3, y = 45. Work out the positive value of x when y = 245.

The point (8, 15) lies on the circle x² + y² = 289. Work out the gradient of the tangent to the circle at that point.The point (8, 15) lies on the circle x^2 + y^2 = 289. Work out the gradient of the tangent to the circle at that point.