Division
Key points
Division is multiplication turned around
12 ÷ 3 is really asking, "3 × □ = 12, so what is □?" That means if you know your times tables, you already know how to divide.
Two ways of sharing
Division can mean two different things. (1) Split 12 things between 3 people — how many does each person get? (2) Hand out 12 things, 3 at a time — how many people get some? Both are written 12 ÷ 3, but the question being asked is not the same.
Think about what the remainder means
35 people need to ride the bus. Each bus holds 8, and 35 ÷ 8 = 4 remainder 3. But the answer is not 4 buses — the 3 people left over still need a ride, so you need 5. What you do with a remainder depends on what the question is actually about.
Only 3 people ride the 5th bus, but you still need that bus.
Compare by finding the price for one
Which is the better deal: 5 for ¥400, or 3 for ¥260? Work out the price of one and you get ¥80 versus about ¥87. Once both are "price for one," you can compare them directly. This is how you spot a good deal in a shop.
Check yourself 5questions
Tap an option to check
Q1 24 candies are shared equally among 6 people. How many does each person get?
Q2 35 people are riding buses that hold 8 each. How many buses are needed?
Q3 Which number sentence means the same thing as 12 ÷ 3?
Q4 Tomatoes cost ¥400 for 5. How much is one tomato?
Q5 What is the remainder of 20 ÷ 6?
Jobs that use this
Every job uses this. The ones below are just where it shows up most.
School teacher$58k
Splitting a class into groups, getting one set of materials per student, dividing up the lesson time — a teacher is dividing, and deciding what to do with the leftovers, all day long.
Maths used: DivisionRemaindersAverages
Delivery route planner$60k
They work out how many trucks the packages need and how many go on each truck. Whether you send out an extra truck for one leftover package can decide whether the job makes money.
Maths used: DivisionRemaindersOptimization
Retail buyer$65k
They convert every offer into "price for one" so they can compare suppliers. Without that unit price in front of you, it is easy to pick the more expensive deal by mistake.
Maths used: DivisionUnit ratesProportions
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