This week the year 3 mental arithmetic questions are all about multiplication and division, including finding quarters. When asked to find a quarter of a number often one of the best approaches is to halve the number and halve again.This works best with even numbers
Some of the multiplication questions look at knowledge of tables, such as 4 times 4, but some of the later questions require this knowledge to be put into use to work out mentally some trickier questions, such as 13 times 3.
There are several ways that 13 times 3 can be approached. One way is to use known facts such as 10 x 3 is 30 and 3 x 3 is 9. Another way is to double 13, making 26 and then adding another 13 to get to 39. Once again it is worth saying that asking children how they reach an answer reveals an awful lot about their knowledge of maths. Unfortunately teachers in a class of 30 children do not have the time to do this with each individual child so it is important to do it at home!
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