Calculate the standard deviation of the following data: 7, 8, 9, 10, 11, 12, 13

A room is 12m long, 9m wide and 8m high. Find the cosine of the angle which a diagonal of the room makes with the floor of the room

What is the circumference of latitude 0o o S if R is the radius of the earth?

Find all median of the numbers 89, 141, 130, 161, 120, 131, 131, 100, 108 and 119

Find all real number x which satisfy the inequality 13 1 3 (x + 1) - 1 > 15 1 5 (x + 4)

Factorise (4a + 3) 2 2 - (3a - 2)2

Four boys and ten girls can cut a field first in 5 hours. If the boys work at 54 5 4 the rate at which the girls work, how many boys will be needed to cut th...

Reach each number to two significant figures and then evaluate 0.02174×1.20470.023789

Evaluate (212)3 3 - (121)3 3 + (222)3