คำตอบ - Long subtraction
329.42
คำอธิบายทีละขั้นตอน
1. Rewrite the numbers from top to bottom, aligned by their place values
| Place value | hundreds | tens | ones | . | tenths | hundredths |
| 3 | 3 | 6 | . | 5 | 2 | |
| - | 7 | . | 1 | |||
| . |
Put zeros in the blank number places:
| Place value | hundreds | tens | ones | . | tenths | hundredths |
| 3 | 3 | 6 | . | 5 | 2 | |
| - | 7 | . | 1 | 0 | ||
| . |
2. Subtract the numbers using long subtraction method
Subtract the numbers in the hundredths column from the top number:
2-0=2
| Place value | hundreds | tens | ones | . | tenths | hundredths |
| 3 | 3 | 6 | . | 5 | 2 | |
| - | 7 | . | 1 | 0 | ||
| . | 2 |
Subtract the numbers in the tenths column from the top number:
5-1=4
| Place value | hundreds | tens | ones | . | tenths | hundredths |
| 3 | 3 | 6 | . | 5 | 2 | |
| - | 7 | . | 1 | 0 | ||
| . | 4 | 2 |
Because the upper digit (6) in the ones column is too small to get a positive difference, borrow 1 from the digit (3) in the next number place which becomes (2) and get (16).
| Place value | hundreds | tens | ones | . | tenths | hundredths |
| 2 | 16 | |||||
| 3 | 3 | 6 | . | 5 | 2 | |
| - | 7 | . | 1 | 0 | ||
| . | 4 | 2 |
Subtract the numbers in the ones column from the top number:
16-7=9
| Place value | hundreds | tens | ones | . | tenths | hundredths |
| 2 | 16 | |||||
| 3 | 3 | 6 | . | 5 | 2 | |
| - | 7 | . | 1 | 0 | ||
| 9 | . | 4 | 2 |
Write 2 in the tens place.
| Place value | hundreds | tens | ones | . | tenths | hundredths |
| 2 | 16 | |||||
| 3 | 3 | 6 | . | 5 | 2 | |
| - | 7 | . | 1 | 0 | ||
| 2 | 9 | . | 4 | 2 |
Write 3 in the hundreds place.
| Place value | hundreds | tens | ones | . | tenths | hundredths |
| 2 | 16 | |||||
| 3 | 3 | 6 | . | 5 | 2 | |
| - | 7 | . | 1 | 0 | ||
| 3 | 2 | 9 | . | 4 | 2 |
The solution is: 329.42
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