72
Multi-step expressions
Textbook Part 2, pp. 64–65
GoalRead, write and work out expressions with several operations.
New words
multi-step expression · tarkibli ifodaplanetarium · planetariytable · jadval
Explanation
An expression with two or more operations is a multi-step expression: 40 + 15 − 20. Without brackets we work left to right: 40 + 15 = 55, 55 − 20 = 35.
Worked examples
A planetarium received 4 telescopes, 12 maps and 21 discs: 4 + 12 + 21 = 37 items.
A bus had 35 people; 12 got off and 4 got on: 35 − 12 + 4 = 27.
Class activity
Children draw the “path” of an expression in their squared notebook: each operation as an arrow, with the result circled at the end.
Practice
1
40 + 15 − 20 = ?
35
2
35 − 12 + 4 = ?
27
3
68 − 30 − 6 = ?
32
4
Write the expression: take 20 from 50, then add 7.
50 − 20 + 7 = 37