1
Four children, two cakes
Discover Mathematics P3: Term 2, Lessons 81–90
GoalShare two cakes among four children in different ways and show that each child gets the same amount.
New words
share · to divide something into equal parts for different peoplefair share · an equal part for each personwhole · all of one thing, such as one full cake
Explanation
Four children want to share 2 cakes so that everyone gets the same amount. There are several ways. Way one: cut each cake into 2 equal halves. That makes 4 halves, one for each child, so each child gets 1/2 of a cake. Way two: cut each cake into 4 equal fourths. That makes 8 fourths, and each child gets 2 fourths. Way three: use division. Two cakes shared by 4 children is 2 ÷ 4, and each child gets 1/2. The pieces look different, but each child gets the same amount, because 2 fourths of a cake is the same amount as 1/2 of a cake.
Worked examples
Way one: cut both cakes into halves. There are 4 halves for 4 children, so each child gets one half.
Way two: cut both cakes into fourths. There are 8 fourths. Share them out: 8 ÷ 4 = 2, so each child gets 2 fourths.
Three friends share 1 cake equally. Each friend gets 1 of 3 equal parts, which is 1/3 of the cake. If they share 3 cakes among 3 friends, each gets 1 whole cake.
Class activity
Share the flatbread. With an adult, take 2 pieces of flatbread or paper. Show how to share them fairly among 4 people in two different ways. Draw both ways. Do all 4 people get the same amount each time?
Practice
1
Three pizzas are shared equally among 6 children. What fraction of a pizza does each child get?
Cut each pizza into halves to make 6 halves. Each child gets 1/2 of a pizza.
2
Two flatbreads are shared equally among 4 people. How much does each person get?
2 ÷ 4 = 1/2, so each person gets half a flatbread.
3
One cake is shared equally among 4 children. What fraction of the cake does each child get?
Each child gets 1/4 of the cake.
4
Mariam cuts 2 cakes, each into 4 equal pieces, as shown. How many pieces are there, and how many pieces does each of 4 children get?
There are 2 × 4 = 8 pieces. Each child gets 8 ÷ 4 = 2 pieces.
5
Hana gets 1/2 of a cake. Youssef gets 2 fourths of the same size cake. Do they get the same amount?
Yes. 2 fourths of a cake is the same amount as 1/2 of the cake.