BBC Bytesize have self text quizzes with instant marking. Try some of those to identify areas you need to work on

Easier number topics
Harder number topics

Try looking over the revision topics and then try the quiz pages.

You could also look over some of the links I put on this page when we were dealing with the number module.

Distance travelled is equal to the speed times the time taken. So if you drive at an average speed of 30 mph for two and a half hours, you will travel 75 miles. There are three permutations of the formula,

• Distance = Speed x Time
• Time = Distance divided by Speed
• Speed = Distance divided by Time

The formula triangle is often used to help remember these relationships. Just put your finger over the letter you are trying to find, and the triangle tells you what calculation to do for the remaining two letters.

Suppose you want to know the time a journey will take. Cover up T and the triangle reveals D / S or distance divided by the speed you drive at as the required calculation.

A quiz on decimal places, significant figures and rounding might help clarify this area of Number. Calculators give you 10 figures even when you want 3.

0.5 is the same as 50% is the same as a half. You need to know about fractions. Those nice people at the BBC Skillswise Web site have built a whole section on fractions, decimals and percentages. Go there!

I’ll be adding some worksheets and revision stuff on fractions here over the weekend.

BBC Byte Size Maths GCSE material on significant figures: read this and then try the Significant Figures Quiz.

You also need to know how to round to a given number of decimal places.

BBC Skillswise has a good page on decimal arithmetic. You should try the quiz at Level A and Level B.

The Highest Common Factor (HCF) and the Lowest Common Multiple (LCM) are easy once you get used to the names.

• HCF of 8 and 12 is 4. The HCF is smaller than the numbers.
• LCM of 8 and 12 is 24. The LCM is larger than the numbers.

Page with notes and interactive exercises :: you can try to answer the questions as you go along and then check your answers. This page explains both the ‘common sense’ method and the ‘prime factors’ method.

The links below might help. These links have buttons to click on the page, so you can get instant marking on examples.

• About Factors and Prime Numbers
• Finding the prime factors of a number using ‘factor trees’
• Prime Factors quiz from BBC Byte Size

The adding and subtracting games from the BBC Skillswise site use an interesting approach to ’splitting’ the numbers down into 100s, 10s and units. Try this, but watch you don’t get confused. There is also a multiplication game.

For those who are confident, try these multiplications - you can click at the bottom to get the answers. Try these long divisions.