### Picture Story

Can you see how this picture illustrates the formula for the sum of the first six cube numbers?

### There and Back

Brian swims at twice the speed that a river is flowing, downstream from one moored boat to another and back again, taking 12 minutes altogether. How long would it have taken him in still water?

### Doesn't Add Up

In this problem we are faced with an apparently easy area problem, but it has gone horribly wrong! What happened?

# Table Total

##### Age 14 to 16 ShortChallenge Level

Adding up all of the numbers and symbols in the table
Total =  + 4 + ( + 4) + 8 +  + ( + 8) + ( + 8) + ( + 4) + 16

= 3$\times$ + 3$\times$ + 52

Bottom row (or last column):
( + 8) + ( + 4) = 16, so  +  + 12 = 16, so  +  = 4

Then, multiplying by 3,
3$\times$ + 3$\times$ = 12

So Total = 12 + 52 = 64

Using the rules in the table to find the total
Reds add up to 16
Yellows add up to 16         Purples add up to yellows

Total = 16$\times$4 = 64

You can find more short problems, arranged by curriculum topic, in our short problems collection.