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## 'Clapping Times' printed from http://nrich.maths.org/

For this activity, you'll need to work with a partner, so the first
thing to do is find a friend!

Together count from $1$ up to $20$, clapping on each number, but
clapping more loudly and speaking loudly on the numbers in the two
times table, and quietly on the other numbers.

Now clap the five times table together up to about $30$, so this
time you are clapping more loudly and speaking loudly on the
multiples of five and quietly on the others.

If one of you claps the twos in this way and one of you claps the
fives, at the same time, can you predict what you would hear?

Which numbers would be quiet?

Which numbers would be fairly loud and which would be very
loud?

Now try it - what did you hear?

Were you right?

Choose another pair of tables and repeat what you have just
done.

How about the twos and tens?

Why not try the fives and tens?

Each time predict what you will hear before you clap - which
numbers will be loud, which fairly loud and which quiet?

If you've enjoyed this activity and would like more of a challenge,
try

Music to my Ears .