Question 344 of 480
What is the result of adding the fractions 3/4 and 2/5?
Correct Answer:
B
Explanation
To find the result of adding the fractions \( \frac{3}{4} \) and \( \frac{2}{5} \), we need to follow a series of steps to ensure we perform the addition correctly. Let's go through this step-by-step.
### Step 1: Find a Common Denominator
When adding fractions, we need to have a common denominator. The denominators in our fractions are 4 and 5. The least common multiple (LCM) of 4 and 5 is 20. This will be our common denominator.
### Step 2: Convert Each Fraction
Next, we need to convert each fraction to have this common denominator of 20.
1. **Convert \( \frac{3}{4} \)**:
- To convert \( \frac{3}{4} \) to a fraction with a denominator of 20, we can multiply both the numerator and the denominator by 5 (since \( 4 \times 5 = 20 \)):
\[
\frac{3}{4} = \frac{3 \times 5}{4 \times 5} = \frac{15}{20}
\]
2. **Convert \( \frac{2}{5} \)**:
- To convert \( \frac{2}{5} \) to a fraction with a denominator of 20, we can multiply both the numerator and the denominator by 4 (since \( 5 \times 4 = 20 \)):
\[
\frac{2}{5} = \frac{2 \times 4}{5 \times 4} = \frac{8}{20}
\]
### Step 3: Add the Converted Fractions
Now that both fractions have the same denominator, we can add them:
\[
\frac{15}{20} + \frac{8}{20} = \frac{15 + 8}{20} = \frac{23}{20}
\]
### Step 4: Simplify if Necessary
In this case, \( \frac{23}{20} \) is already in its simplest form. It is an improper fraction, which means the numerator is greater than the denominator. If needed, it can also be expressed as a mixed number:
\[
\frac{23}{20} = 1 \frac{3}{20}
\]
### Conclusion
The result of adding \( \frac{3}{4} \) and \( \frac{2}{5} \) is \( \frac{23}{20} \).
### Explanation of Options
- **Option A: \( \frac{7}{20} \)** - This is incorrect because it does not represent the sum of the two fractions. It seems to be a miscalculation.
- **Option B: \( \frac{23}{20} \)** - This is the correct answer, as shown in our calculations.
- **Option C: \( \frac{13}{20} \)** - This is also incorrect. It may arise from an incorrect addition or misunderstanding of the common denominator.
- **Option D: \( \frac{1}{5} \)** - This is incorrect as it is far less than the sum of the two fractions and does not relate to the problem.
### Revision Summary
- To add fractions, find a common denominator.
- Convert each fraction to have the common denominator.
- Add the numerators while keeping the common denominator.
- Simplify the result if necessary.
The correct answer is **B: \( \frac{23}{20} \)**.