Daily Practice - Higher Plus

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.

A bag holds 7 red, 4 blue and 5 green counters. Two are taken without replacement. Given neither is green, what is the probability both are red?

On a histogram, a 5-wide bar and a 10-wide bar have the same frequency density of 2.5. How many more values are in the wider class?

A rectangle is 15 cm by 10 cm, each correct to the nearest cm. Work out the upper bound of its area.

The curve y = sin x° is drawn for 0 ≤ x ≤ 360. Write down the value of y when x = 90.The curve y = sin x° is drawn for 0 <= x <= 360. Write down the value of y when x = 90.