82 Speed Math for Kids
We can also write another 0 before the decimal, because there should
always be at least one digit before the decimal. Our answer would
now look like this:
0.0182
Let’s try some more:
0.014 × 1.4 =
14 × 14 = 196
Where do we put the decimal? Th ere are four digits after the decimal
in the problem; 0, 1 and 4 in the fi rst number and 4 in the second,
so we must have four digits after the decimal in the answer. Because
there are only three digits in our answer, we supply a 0 to make the
fourth digit.
Our answer is 0.0196.
Test you rself
Try these for yourself:
a) 22 × 2.4 =
b) 0.48 × 4.8 =
c) 0.048 × 0.48 =
d) 0.0023 × 0.23 =
Easy, wasn’t it? Here are the answers:
a) 52.8 b) 2.304 c) 0.02304 d) 0.000529
Beating the system
Understanding this simple principle can help us solve some problems
that appear diffi cult using our method but can be adapted to make
them easy. Here is an example.
8 × 79 =
brent
(Brent)
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