Multiplying Two Numbers Together, Only One Of Them Ends In “0”
If one of the numbers doesn’t end with “0” there still might be a way to use this sort of skill, combined with your excellent knowledge of the “times tables” to do TWO sums in your head, and add the results together.
Here’s an example:
“twenty-six times forty” is the same as “twenty-six forties” isn’t it? in that case why not split this in half so there are two sums, but both are easier, then we add the results together?
Can you see what I say here? …….
Both of these smaller sums can be done by moving the “0” just like before:
Here’s another one:
Do what we did last time…. Split it up:
Move the “0” s just like before:
Examples: You try these now ….
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Here’s the one highlighted in red… as a starter:
Self Test Answers:
25 x 20 |
500 |
60 x 45 |
2700 |
32 x 50 |
1600 |
28 x 90 |
2520 |
100 x 56 |
5600 |
38 x 200 |
7600 |
17 x 500 |
8500 |
11 x 900 |
9900 |
300 x 64 |
19200 |
250 x 35 |
8750 |
73 x 250 |
18250 |
97 x 120 |
11640 |