142
Year review: problems and calculation
Textbook Part 4, pp. 64–65
GoalConsolidate the calculation and problem-solving skills learned this year.
New words
review · takrorlashsupermarket · supermarkettowel · sochiq
Explanation
In review we recall every kind of problem: whole (add), part (subtract), more/fewer, how many more, equations. Drawing a diagram helps decide which operation is needed.
Worked examples
Shelf 1 has 23 boxes of toothpaste and shelf 2 has 34; all three shelves hold 78: 78 − (23 + 34) = 78 − 57 = 21 boxes.
Of 19 towels, 8 are bath towels: 19 − 8 = 11 hand towels.
Class activity
“Supermarket” role play: children are sellers and shoppers and work out totals and change from price tags (up to 100).
Practice
1
78 − (23 + 34) = ?
21
2
19 − 8 = ?
11
3
Put the answers in increasing order: 45 + 32, 90 − 50, 8 + 9
17, 40, 77
4
Match: “unit of mass” — ?
kilogram