### Look Before You Leap

Relate these algebraic expressions to geometrical diagrams.

### Modular Fractions

We only need 7 numbers for modulus (or clock) arithmetic mod 7 including working with fractions. Explore how to divide numbers and write fractions in modulus arithemtic.

### All Tangled Up

Can you tangle yourself up and reach any fraction?

# Can it Be

##### Age 16 to 18 Challenge Level:
Assume it is a valid formula, then what does this tell you about $a$, $b$, $c$ and $d$?