How do you remember how many sides a pentagon has?

Answer 1

Penta is a common prefix meaning five. One way to memorize lists of things is to make a set of cards (pieces of cardbord, perhaps 3 x 5 inches or so - that would be about 7 x 12 cm), with (in this case) the prefix on one side, and the definition on the other side. Go through them, and try to remember the definition. Whether you remember it or not, look at the answer. After a while, you can put aside those cards which you know well, and continue with those you don't.

Here are some common prefixes for numbers:

mono - 1

bi (or di) - 2

tri - 3

tetra - 4

penta - 5

hexa - 6

hepta - 7

octo - 8

nona - 9

deka - 10