คำตอบ - Long subtraction
คำอธิบายทีละขั้นตอน
1. Rewrite the numbers from top to bottom, aligned by their place values
| Place value | tens | ones | . | tenths | hundredths | thousandths | ten thousandths |
| 4 | 7 | . | 3 | 0 | 3 | 1 | |
| - | 9 | . | 0 | 0 | 9 | ||
| . |
Put zeros in the blank number places:
| Place value | tens | ones | . | tenths | hundredths | thousandths | ten thousandths |
| 4 | 7 | . | 3 | 0 | 3 | 1 | |
| - | 9 | . | 0 | 0 | 9 | 0 | |
| . |
2. Subtract the numbers using long subtraction method
Subtract the numbers in the ten thousandths column from the top number:
1-0=1
| Place value | tens | ones | . | tenths | hundredths | thousandths | ten thousandths |
| 4 | 7 | . | 3 | 0 | 3 | 1 | |
| - | 9 | . | 0 | 0 | 9 | 0 | |
| . | 1 |
Because the upper digit (3) in the thousandths column is too small to get a positive difference, borrow 1 from the number to the left (30) which becomes (29) and get (13).
| Place value | tens | ones | . | tenths | hundredths | thousandths | ten thousandths |
| 2 | 9 | 13 | |||||
| 4 | 7 | . | 3 | 0 | 3 | 1 | |
| - | 9 | . | 0 | 0 | 9 | 0 | |
| . | 1 |
Subtract the numbers in the thousandths column from the top number:
13-9=4
| Place value | tens | ones | . | tenths | hundredths | thousandths | ten thousandths |
| 2 | 9 | 13 | |||||
| 4 | 7 | . | 3 | 0 | 3 | 1 | |
| - | 9 | . | 0 | 0 | 9 | 0 | |
| . | 4 | 1 |
Subtract the numbers in the hundredths column from the top number:
9-0=9
| Place value | tens | ones | . | tenths | hundredths | thousandths | ten thousandths |
| 2 | 9 | 13 | |||||
| 4 | 7 | . | 3 | 0 | 3 | 1 | |
| - | 9 | . | 0 | 0 | 9 | 0 | |
| . | 9 | 4 | 1 |
Subtract the numbers in the tenths column from the top number:
2-0=2
| Place value | tens | ones | . | tenths | hundredths | thousandths | ten thousandths |
| 2 | 9 | 13 | |||||
| 4 | 7 | . | 3 | 0 | 3 | 1 | |
| - | 9 | . | 0 | 0 | 9 | 0 | |
| . | 2 | 9 | 4 | 1 |
Because the upper digit (7) in the ones column is too small to get a positive difference, borrow 1 from the digit (4) in the next number place which becomes (3) and get (17).
| Place value | tens | ones | . | tenths | hundredths | thousandths | ten thousandths |
| 3 | 17 | ||||||
| 2 | 9 | 13 | |||||
| 4 | 7 | . | 3 | 0 | 3 | 1 | |
| - | 9 | . | 0 | 0 | 9 | 0 | |
| . | 2 | 9 | 4 | 1 |
Subtract the numbers in the ones column from the top number:
17-9=8
| Place value | tens | ones | . | tenths | hundredths | thousandths | ten thousandths |
| 3 | 17 | ||||||
| 2 | 9 | 13 | |||||
| 4 | 7 | . | 3 | 0 | 3 | 1 | |
| - | 9 | . | 0 | 0 | 9 | 0 | |
| 8 | . | 2 | 9 | 4 | 1 |
Write 3 in the tens place.
| Place value | tens | ones | . | tenths | hundredths | thousandths | ten thousandths |
| 3 | 17 | ||||||
| 2 | 9 | 13 | |||||
| 4 | 7 | . | 3 | 0 | 3 | 1 | |
| - | 9 | . | 0 | 0 | 9 | 0 | |
| 3 | 8 | . | 2 | 9 | 4 | 1 |
The solution is: 38.2941
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