Higher Plus

On a histogram, a 10-wide bar and a 30-wide bar have the same frequency density of 2. How many more values are in the wider class?

A block has mass 260 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 260 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.

Solve 4x² + 15x - 25 = 0.Solve 4x^2 + 15x - 25 = 0.

A cyclist speeds up steadily from 9 m/s to 15 m/s over 10 seconds. Use the area under the velocity-time graph to find the distance travelled.

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.