Idea 23of 23Builds onSubtraction undoes additionEstimate to check an answer
Solve a problem in two steps
How much is left after two things are paid for?
Today you'll discover
- how a bar shows the problem
- which step comes first
- how to check the answer
Think firstA $50 000 park budget
$18 750 goes on a playground and $12 400 on trees. How much is left?
Decide first, then press Next. Ask which number the question wants.
A $50 000 bar split into $18 750, $12 400 and a piece marked with a question mark. A second bar brackets the first two pieces as spent: $31 150. Then $18 750 + $12 400 = $31 150 and $50 000 − $31 150 = $18 850, and the check $18 750 + $12 400 + $18 850 = $50 000. The last step shows a $12 000 school fund.
See the whole ideathe big idea and the key word, in one place
The big idea
Solve one step at a time: add what was spent, then subtract it from the whole.
Compare themRead what the question asks. The first step finds what was spent; the answer is what is left.
Key word
- two-step problem
- a problem that needs two calculations, the answer to the first used in the second
Ready to use it?
- Solve a two-step problem with a bar model.