Higher Plus

A histogram has two bars: one 20 units wide with frequency density 2, one 25 units wide with density 1.4. How many values in total?

Rationalise the denominator of 10/2, giving your answer in its simplest form.Rationalise the denominator of 10/sqrt(2), giving your answer in its simplest form.

Solve x² + y² = 841 and y = x + 1 simultaneously.Solve x^2 + y^2 = 841 and y = x + 1 simultaneously.

y is directly proportional to x². When x = 5, y = 100. Work out the positive value of x when y = 256.y is directly proportional to x^2. When x = 5, y = 100. Work out the positive value of x when y = 256.

In a circle theorem proof, a step uses the fact that the three angles of triangle OAB are being summed. State the reason being quoted.