B2.8 Multiply and divide one-digit whole numbers by unit fractions, using appropriate tools and drawings.
Activity 1: Should I Multiply or I Divide?
The relay race is a very popular at end-of-year sports activity. The total distance of the race is 3 km. Each person runs for \(\frac{1}{2}\) km. How many people are in each team?
Source: inspired by and translated from En avant, les maths! 5e, ML, Nombres.
Activity 2: Division
Louisa must separate the 7 m of fabric she bought into thirds of a metre. How many thirds of a metre will she have?
We need to find out how many thirds of a metre Louisa can make. The question to ask is: When 7 m is divided into thirds of a metre, how many thirds are there?
There are 21 thirds when we divide 7 into thirds. So, \(7\; \div \;\frac{1}{3}\; = \;21\). Louisa will therefore have 21 thirds of a metre when she divides the 7 metres into thirds of a metre.
Source: translated from L’@telier - Ressources pédagogiques en ligne (atelier.on.ca).
Activity 3: How Many Canned Fruit?
Mom counts 8 cans of food in the cupboard. Canned fruit makes up one fourth of those cans. How many cans of canned fruit does she have?