Multi-Step Multiply & Divide
Solve problems involving multiplication and division, including scaling problems and correspondence problems where n objects are connected to m objects
What a learner can do afterwards
- Solve a scaling problem (e.g. 'the ribbon is 3 times as long')
- Solve a correspondence problem (e.g. '4 shirts and 3 trousers — how many outfits?')
- Solve a missing-number multiplication or division problem
The lesson
Some problems need two steps, not one. A ribbon might be described as '3 times as long' as another one, that's a scaling problem. Or two groups of things might get matched together, like shirts with trousers, that's a correspondence problem. Once you know which kind of problem it is, you know which operation to use.
Zara has 4 shirts and 3 pairs of trousers. Any shirt can go with any pair of trousers. To find how many outfits she can make, multiply the two numbers: 4 x 3 = 12 outfits.
If a number is missing from a multiplication, use division to find it, and the other way round. For 3 x ? = 15, work backwards: 15 / 3 = 5.
Scaling means multiply by how many times bigger. Matching means multiply the two group sizes. A missing number problem uses the opposite operation to find the answer.
Watch it
Where it sits
8 questions wait behind this lesson, each with its answer explained. Every answer feeds the sky: stars light as they are learned, and dim when it is time to come back.