With the 11+ exams fast approaching, my students are putting the finishing touches on their 11+ maths knowledge.  There are certain key facts that it's difficult to do without.  I've collected a few of them in this post.

fraction facts to know
clock w: angle

The angle between hours on a normal clock is 30º

angles
fraction facts

1000cm³ = 1 litre 1m³ = 1,000,000cm³ (this one always catches people out)
60 seconds in a minute; 60 minutes in an hour;
24 hours in a day; 52 weeks in a year; 365 days in a year.  (4.35 weeks in a month)
1km = 1000m 100cm = 1m 10mm = 1cm

Imagine you are given some input and outputs (as below) and asked to find the rule for the number machine.  You should do the following:

Find the volume and surface area of a 9x8x4cm cuboid.

Volume = 9x8x4 = 288cm³  (multiply all dimensions together)

Surface Area = you need to think about the net of your cuboid.  The net will be made out of 3 pairs of identical rectangles, as shown below.

So surface area = (9x8 + 9x4 + 8x4) x2 = (72+36+32)x2 = 140x2 = 280cm²

Memorise the first few primes: 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31.
Memorise the first few square numbers: 1, 4, 9, 16, 25, 36, 49, 64, 81, 100, 121, 144, 169, 196, 225.
Memorise the first few cube numbers: 1, 8, 27, 64, 125

Make sure you can express numbers as products of their prime factors; there's a guide to prime factors for 11+ in this blog post

## Conclusion:

Knowing these facts will not guarantee you success at 11+. There is plenty more to know, and the ability to problem solve under pressure is crucial too. Nevertheless, running through this list should be very helpful.