Lesson 3 of 16
Work out each term first
Show on a big screenA chit — a small bill — says 45 − 3 × 8 + 9. Where does one piece end and the next begin?
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Step 1 of 5
- The line: 45 − 3 × 8 + 9.
- Cut it into terms: 45, −3 × 8, 9.
- Work out the term with ×: 3 × 8 = 24.
- The line is now 45 − 24 + 9.
- Add the terms. The value is 30.
The rule
A piece ends just before the next + or −.
A term is a piece that gets added. Read each − as adding a negative number.
The − stays with the number after it. So 45 − 3 × 8 + 9 has three terms. They are 45, −3 × 8 and 9.
Work out each term first. Then add the terms.
So × and ÷ inside a term go before + and −.
| The line | Terms | Value |
|---|---|---|
| 7 + 4 × 3 | 7, 4 × 3 | 19 |
| 20 − 6 ÷ 2 | 20, −6 ÷ 2 | 17 |
| 5 × 7 + 3 × 4 | 5 × 7, 3 × 4 | 47 |
Try the lab to finish this lesson.