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?

Simplify 80 + 45, giving your answer in the form a b.Simplify sqrt(80) + sqrt(45), giving your answer in the form a sqrt(b).

Make x the subject of 3x + 2 = y(x + 2).

A cyclist speeds up steadily from 5 m/s to 24 m/s over 8 seconds. Use the area under the velocity-time graph to find the distance travelled.

The point (6, 8) lies on the circle x² + y² = 100. Work out the gradient of the tangent to the circle at that point.The point (6, 8) lies on the circle x^2 + y^2 = 100. Work out the gradient of the tangent to the circle at that point.