Convert (i) `1 3/4` and (ii) `3 4/5` as improper fraction.

Explanation

To convert the mixed numbers \(1 \frac{3}{4}\) and \(3 \frac{4}{5}\) into improper fractions, we can follow these steps:

### Step 1: Convert \(1 \frac{3}{4}\) to an improper fraction
1. **Multiply the whole number by the denominator**:
- The whole number is \(1\) and the denominator of the fraction \(\frac{3}{4}\) is \(4\).
- Calculation: \(1 \times 4 = 4\).

2. **Add the numerator of the fraction to the result**:
- The numerator of the fraction is \(3\).
- Calculation: \(4 + 3 = 7\).

3. **Write the result over the original denominator**:
- The denominator remains \(4\).
- Therefore, \(1 \frac{3}{4} = \frac{7}{4}\).

### Step 2: Convert \(3 \frac{4}{5}\) to an improper fraction
1. **Multiply the whole number by the denominator**:
- The whole number is \(3\) and the denominator of the fraction \(\frac{4}{5}\) is \(5\).
- Calculation: \(3 \times 5 = 15\).

2. **Add the numerator of the fraction to the result**:
- The numerator of the fraction is \(4\).
- Calculation: \(15 + 4 = 19\).

3. **Write the result over the original denominator**:
- The denominator remains \(5\).
- Therefore, \(3 \frac{4}{5} = \frac{19}{5}\).

### Final Answers:
- \(1 \frac{3}{4} = \frac{7}{4}\)
- \(3 \frac{4}{5} = \frac{19}{5}\)

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