THE TRANSITION LINE // FIELD NOTES // STOP 09
Percents and decimals become fractions
Field Book
Lessons 33 to 36
Method
Pencil and paper. Calculators never.
The exchange window: every form of a number trades at par. A percent is a count out of 100 and drops straight over 100, a decimal drops over its furthest place value, decimal numbers get read aloud with AND at the point, and a fraction worth one becomes the year's favorite trading piece.
What you have to be able to do
- Change percents to reduced fractions
- Change decimals to reduced fractions
- Read and write decimal numbers in words
- Regroup a mixed number using a fraction worth one
The procedures
Percent to fractionField Book Lesson 33
- Place the percent over 100.
- Reduce.
Decimal to fractionField Book Lesson 34
- Write the decimal part over its furthest place value.
- Reduce.
Decimals in wordsField Book Lesson 35
- Say the whole number, say AND at the point.
- Name the decimal part as a single fraction over its place.
Fractions worth oneField Book Lesson 36
- Any fraction with matching top and bottom is worth exactly 1.
- To make room for subtracting, exchange 1 from the whole number for a fraction worth 1.
Worked: 45 percent on the record
- 45% = 45100
- Reduce by 5: 920.
Worked: exchange a one
- 5 16 needs a bigger fraction part.
- Exchange: 5 16 = 4 76.
Terms on the record
| Term | Meaning |
|---|
| percent | a count out of 100 |
| fraction worth one | a fraction whose top equals its bottom |
| regrouping | exchanging 1 for a fraction worth 1, or a fraction worth 1 for a 1 |