Numeracy problems to solve for Key Stage 1, 2 and 3

Emily has four coloured counters. Red, blue, green and yellow.

She decides to arrange them side by side in a row.

How many different ways could she arrange them?

If you can't pay for it with Pentas and Septies you get it FREE!

The money on the planet Ziggus has only two coins: the septie worth 7 zig and the penta worth 5 zigs. (A zig is the unit of currency like the euro or pound.) All things in the shops are priced so that they can be paid for without the need ever to give change. If a ziggusian spots something that can't be paid for exactly, using multiples of the two coins, they get if FREE!

Helmet 58 zigs

Candy 13 zigs

Marbles 36 zigs

Snooker Table 97 zigs

Which of these things can't be paid for exactly?
Can you work out what amounts under 100 can be made with the two ziggusian coins? Which number can't be made?