### Shortcut Methods

**JEE Main**

**1.** The absolute error in the measurement is half of the smallest division on the meter rule, which is 0.05 cm.

**2.** The relative error in the measurement is the absolute error divided by the measured value, which is:

```
(0.0025 g) / (50.025 g) = 5 × 10-5
```

**3.** The percentage error in the measurement is the relative error multiplied by 100%, which is:

```
(5 × 10-5) × 100% = 0.005%
```

**CBSE Board Exams**

**1.** The percentage uncertainty in the measurement is the uncertainty divided by the measured value, multiplied by 100%, which is:

```
(0.1 cm) / (20.3 cm) × 100% = 0.5%
```

**2.** The percentage uncertainty in the measurement is the uncertainty divided by the measured value, multiplied by 100%, which is:

```
(5 g) / (1000 g) × 100% = 0.5%
```

**3.** The percentage uncertainty in the measurement is the uncertainty divided by the measured value, multiplied by 100%, which is:

```
(1 minute) / (2 hours × 60 minutes) × 100% = 0.083%
```