Fractions of a whole (age 9+)
Solve word problems involving multiplication of a fraction by a whole number using visual models and equations
What a learner can do afterwards
- Each person eats 3/8 of a pizza and there are 5 people — how many pizzas are needed?
- A ribbon is cut into pieces of 2/3 metre; how long are 4 pieces altogether?
- Between what two whole numbers does 6 × 3/4 lie?
The lesson
You already know how to multiply a fraction by a whole number. In a word problem, the hard part is spotting which numbers to multiply. Look for a fraction that repeats, like 'each person eats 3/8', and a whole number that says how many times, like '5 people'. Multiply those two together to get the total.
Four ribbon pieces are each 2/3 metre. The equation is 4 x 2/3. Multiply: 4 x 2/3 = 8/3 = 2 and 2/3 metres altogether.
Six friends each eat 3/8 of a pizza. The equation is 6 x 3/8 = 18/8 = 2 and 1/4 pizzas' worth. Pizzas only come whole, so you need to round up to 3 pizzas so nobody goes hungry.
To find which two whole numbers an answer sits between, do the multiplication first, then look at the mixed number: 6 x 3/4 = 18/4 = 4 and 1/2, so it lies between 4 and 5.
Turn the word problem into a fraction times a whole number, solve it, then think about what the answer means in real life.
Watch it
Where it sits
Learn first
This opens up
Where this leads
Jobs that lean on this skill. Follow one to see everything it is built on.
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.