Answer :
When adding or subtracting measurements, it’s important to consider the number of significant figures, especially with decimal places. Here’s a step-by-step explanation for each operation:
1. Addition: 19.77 mL + 17.827 mL
- First, line up the measurements by their decimal points:
```
19.77
+17.827
```
- Perform the addition:
```
37.597
```
- Since 19.77 has two decimal places, the result should be rounded to two decimal places:
```
37.60 mL
```
2. Addition: 18.80 mL + 3.607 mL
- First, line up the measurements by their decimal points:
```
18.80
+ 3.607
```
- Perform the addition:
```
22.407
```
- Since 18.80 has two decimal places, the result should be rounded to two decimal places:
```
22.41 mL
```
3. Subtraction: 19.87 mL - 2.507 mL
- First, line up the measurements by their decimal points:
```
19.870
- 2.507
```
- Perform the subtraction:
```
17.363
```
- Since 19.87 has two decimal places, the result should be rounded to two decimal places:
```
17.36 mL
```
In summary, the results of the calculations with the correct number of significant figures are:
- [tex]\( 19.77 \, \text{mL} + 17.827 \, \text{mL} = 37.60 \, \text{mL} \)[/tex]
- [tex]\( 18.80 \, \text{mL} + 3.607 \, \text{mL} = 22.41 \, \text{mL} \)[/tex]
- [tex]\( 19.87 \, \text{mL} - 2.507 \, \text{mL} = 17.36 \, \text{mL} \)[/tex]
1. Addition: 19.77 mL + 17.827 mL
- First, line up the measurements by their decimal points:
```
19.77
+17.827
```
- Perform the addition:
```
37.597
```
- Since 19.77 has two decimal places, the result should be rounded to two decimal places:
```
37.60 mL
```
2. Addition: 18.80 mL + 3.607 mL
- First, line up the measurements by their decimal points:
```
18.80
+ 3.607
```
- Perform the addition:
```
22.407
```
- Since 18.80 has two decimal places, the result should be rounded to two decimal places:
```
22.41 mL
```
3. Subtraction: 19.87 mL - 2.507 mL
- First, line up the measurements by their decimal points:
```
19.870
- 2.507
```
- Perform the subtraction:
```
17.363
```
- Since 19.87 has two decimal places, the result should be rounded to two decimal places:
```
17.36 mL
```
In summary, the results of the calculations with the correct number of significant figures are:
- [tex]\( 19.77 \, \text{mL} + 17.827 \, \text{mL} = 37.60 \, \text{mL} \)[/tex]
- [tex]\( 18.80 \, \text{mL} + 3.607 \, \text{mL} = 22.41 \, \text{mL} \)[/tex]
- [tex]\( 19.87 \, \text{mL} - 2.507 \, \text{mL} = 17.36 \, \text{mL} \)[/tex]
