Sum Equals Product

The sum of the numbers 4 and 1 [1/3] is the same as the product of 4 and 1 [1/3]; that is to say 4 + 1 [1/3] = 4 � 1 [1/3]. What other numbers have the sum equal to the product and can this be so for any whole numbers?
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Problem



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?