### Back to School

Mr. Sunshine tells the children they will have 2 hours of homework. After several calculations, Harry says he hasn't got time to do this homework. Can you see where his reasoning is wrong?

### The Magic Number and the Hepta-tree

Find the exact difference between the largest ball and the smallest ball on the Hepta Tree and then use this to work out the MAGIC NUMBER!

### Shedding Some Light

Make an estimate of how many light fittings you can see. Was your estimate a good one? How can you decide?

# What's My Weight?

##### Stage: 2 Short Challenge Level:

We had a solution to this problem from someone who didn't give their name or school - but thank you!

From the picture of the scales, the apple must weigh less than the four weights altogether.
If the apple weighs $180g$, for the scale to be balanced the weights would have to be $45g$ each because there are four of them. But we know from the picture that the apple weighs less than the weights put together, so each weight must be more than $45g$.
If the apple weighed $375g$, then for the scale to be balanced, each weight would be $93.75g$. So, for the weights to be heavier than the apple, each one must be more than $375g$.
One kilo is $1000g$ and four $250g$ weights would also weigh $1000g$ altogether so the scale would be balanced.