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# Sum Equals Product

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### Chocolate

### Tweedle Dum and Tweedle Dee

### Special Sums and Products

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Age 11 to 14

Challenge Level

I have been practising arithmetic with fractions.

I worked out $4 + 1 \frac{1}{3}$ but then realised that I had misread the question!

I was supposed to work out $4 \times 1 \frac{1}{3}$

When I worked out the multiplication, I was surprised to find I got the same answer to both calculations!

Can you find other examples of calculations where replacing the multiplication sign by an addition sign does not alter the result of the calculation?

There are three tables in a room with blocks of chocolate on each. Where would be the best place for each child in the class to sit if they came in one at a time?

Two brothers were left some money, amounting to an exact number of pounds, to divide between them. DEE undertook the division. "But your heap is larger than mine!" cried DUM...

Find some examples of pairs of numbers such that their sum is a factor of their product. eg. 4 + 12 = 16 and 4 × 12 = 48 and 16 is a factor of 48.