Higher Plus

On a histogram, a 10-wide bar and a 30-wide bar have the same frequency density of 2.5. How many more values are in the wider class?

Rationalise the denominator of 48/6, giving your answer in its simplest form.Rationalise the denominator of 48/sqrt(6), giving your answer in its simplest form.

Simplify (x² - 2x - 8)/(x - 4).Simplify (x^2 - 2x - 8)/(x - 4).

A tram runs at 12 m/s for 10 s, then slows steadily to rest over 4 s. Work out its average speed for the whole journey, to 2 decimal places.

The point (5, 12) lies on the circle x² + y² = 169. Work out the gradient of the tangent to the circle at that point.The point (5, 12) lies on the circle x^2 + y^2 = 169. Work out the gradient of the tangent to the circle at that point.