The first line of the calculation is the same procedure as multiplying with a single digit number. In the second line we are multiplying by \(20\) (two tens). As we are multiplying by tens the unit's ...

19 is only 1 away from 20, so you prefer to start by multiplying 20 times 5, which equals 100. Then we need to take away a squadron of 5, because there are actually only 19 squadrons, not 20. 100 take ...

This summer, battle lines were drawn over a simple math problem: 8 ÷ 2(2 + 2) = ? If you divide 8 by 2 first, you get 16, but if you multiply 2 by (2 + 2) first, you get 1. So, which answer is right?

Math isn't always about intricate procedures and drawn-out computations. These five smart multiplication strategies might help students improve their mental math abilities and solve problems more ...

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