A peice of wire is 240cm long. Peter cuts two 45cm lengths off the wire. He then cuts the rest of the wire into as many 40cm lengths as possible. Work out how many 40cm lengths of wire Peter cuts

Use mathematical induction to prove the statement is true for all positive integers n, or show why it is false. 1^2 + 4^2 + 7^2 + + (3n - 2)^2 = [n(6n^2-3n-1)/2]

How is the interquartile range calculated?

Use the linear combination method to solve the system of equations. explain each step of your solution. if steps are not explained, you will not receive credit for that step. 2 + 9 = −26 −3 − 7 = 13