Higher Plus

On a histogram, a 5-wide bar and a 15-wide bar have the same frequency density of 3. How many more values are in the wider class?

Rationalise the denominator of 132/11, giving your answer in its simplest form.Rationalise the denominator of 132/sqrt(11), giving your answer in its simplest form.

Solve x² + y² = 169 and y = x + 7 simultaneously.Solve x^2 + y^2 = 169 and y = x + 7 simultaneously.

A cyclist speeds up steadily from 6 m/s to 10 m/s over 10 seconds. Use the area under the velocity-time graph to find the distance travelled.

The point (20, 21) lies on the circle x² + y² = 841. Work out the gradient of the tangent to the circle at that point.The point (20, 21) lies on the circle x^2 + y^2 = 841. Work out the gradient of the tangent to the circle at that point.