Percentages

To make porridge, Goldilocks mixes oats and wheat bran..... what percentage of the mix is wheat?

Weekly Problem 12 - 2010
Can Emily increase her average test score to more than $80$%? Find out how many more tests she must take to do so.

Can you match the cards and figure out whether the tabloid headlines can be trusted?

Prove that the shaded area of the semicircle is equal to the area of the inner circle.

A political commentator summed up an election result. Given that there were just four candidates and that the figures quoted were exact find the number of votes polled for each candidate.

How much more antifreeze is needed to make the proportion 30%?

What is 50% of 2007 plus 2007% of 50?

Weekly Problem 16 - 2008
A 30cm x 40cm page of a book includes a 2cm margin on each side... What percentage of the page is occupied by the margins?

If the base of a rectangle is increased by 10% and the area is unchanged, by what percentage is the width decreased by ?