Which of the following fractions is less than one-third?

A cuboid has a diagonal of length 9cm and a square base of side 4cm. What is its height?

Evaluate correct to 4 decimal places 827.51 x 0.015

What is the area between two concentric circles of diameters 26cm and 20cm?

Marks scored by some children in an arithmetic test are:5, 3, 6, 9, 4, 7, 8, 6, 2, 7, 8, 4, 5, 2, 1, 0, 6, 9, 0, 8.
The arithmetic mean of the marks is