15-Let’s Add and Subtract by Jumping
The jumping strategy is a key one for mental calculation.
Let’s see how ...
16-Let’s Add and Subtract by Breaking Down
The breaking down strategy is a key one for written calculation.
Let’s see ...
17-Let’s Do Percentages
Percentages are expressions used widely in our daily lives.
Using examples, let’s see ...
18-Let’s Derive Facts
Deducing facts based on others we are already aware of, is a crucial ...
19-Let’s Estimate
On a daily basis, we do not have to make exact calculations very ...