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Voiceover: In a world without maths,a land where people forgot, who will save the day? Narrator: Whether multiplying or dividing, skills like counting in twos, fives and tens are vitally important.

An insomniac girl named Clarissa tries counting sheep to fall sleep, but it has the opposite effect: “A loud baa made her open her eyes, and to her surprise, she saw ten sheep in her room.” Counting ...

Counting in 50s is just like counting in 5s but with an extra zero. This is because the numbers are ten times bigger. There are 350 chocolates in 7 boxes. Another way you could have worked this out is ...