2
Review: time, groups and data
Joyful Mathematics: Chapters 8–13
GoalReview parts of the day, seasons, equal groups and counting data.
New words
equal groups · groups with the same numbermost · the biggest numberseason · a part of the year
Explanation
A day has morning, afternoon, evening and night. The year has summer, monsoon, winter and spring. Equal groups can be added: 3 times 4 means 4 + 4 + 4 = 12. When we count data, we can say more than, less than or equal to. The most is the biggest number and the least is the smallest.
Worked examples
The sun rises and we wake up in the morning. We see the moon at night.
Each tray has 2 seedlings. 5 trays have 10 seedlings.
There are 6 cars, 3 buses and 5 autos. Cars are the most. Buses are the least.
Class activity
Mixed review. Tell your family what you do in each part of the day. Then find 3 equal groups in your home, such as 2 shoes in each pair. Say how many groups and the total.
Practice
1
Which part of the day comes after afternoon?
Evening.
2
What is 3 + 3 + 3 + 3?
12
3
Which bar is the tallest? Which is the shortest?
Mango is the tallest. Apple is the shortest.
4
In which season do we need an umbrella the most?
The monsoon.
5
The number of cats is ___ the number of fish.
more than.