Add or subtract the following measurement be sure each answer you enter contains the correct number of significant digits
5.79mL-1.5mL=?mL
12.8mL+5.970mL=?mL
0.720mL+13.60mL=?mL
5.79 mL - 1.5 mL = 4.29 mL
12.8 mL + 5.970 mL = 18.770 mL
0.720 mL + 13.60 mL = 14.32 mL
To add or subtract measurements with the correct number of significant digits, follow these steps:
1. Determine the measurement with the least number of decimal places. This will determine the number of decimal places in the answer.
2. Perform the addition or subtraction operation as usual, without considering significant digits.
3. Round the answer to the same number of decimal places as the measurement identified in step 1.
Let's calculate the answers with the correct number of significant digits:
1. 5.79 mL - 1.5 mL = 4.29 mL
- The measurement with the least number of decimal places is 1.5 mL, which has one decimal place.
- Perform the subtraction: 5.79 mL - 1.5 mL = 4.29 mL.
- Round the answer to one decimal place, giving us 4.3 mL as the final result.
2. 12.8 mL + 5.970 mL = 18.77 mL
- The measurement with the least number of decimal places is 5.970 mL, which has three decimal places.
- Perform the addition: 12.8 mL + 5.970 mL = 18.770 mL.
- Round the answer to three decimal places, giving us 18.770 mL.
- However, since the significant digits in 12.8 mL are two, the final answer should have two significant digits.
- Therefore, rounding the answer to two significant digits, we get 18 mL.
3. 0.720 mL + 13.60 mL = 14.32 mL
- The measurement with the least number of decimal places is 13.60 mL, which has two decimal places.
- Perform the addition: 0.720 mL + 13.60 mL = 14.320 mL.
- Round the answer to two decimal places, giving us 14.32 mL.
So, the answers are:
1. 5.79 mL - 1.5 mL = 4.3 mL
2. 12.8 mL + 5.970 mL = 18 mL
3. 0.720 mL + 13.60 mL = 14.32 mL