Out of a class of 38 girls, three were absent, `20%` of the remainder failed to do the home work. How many did the home work?

Options

A. 18
B. 20
C. 24
D. 28

Answer

To solve the problem step by step, we can follow these instructions:

### Step 1: Calculate the number of girls present in class
First, we need to determine how many girls were present after accounting for the absentees.

- Total girls in the class = 38
- Number of girls absent = 3

**Calculation:**
\[ \text{Number of girls present} = \text{Total girls} - \text{Absent girls} = 38 - 3 = 35 \]

### Step 2: Calculate the number of girls who failed to do the homework
Next, we need to find out how many of the present girls failed to do their homework. We know that 20% of the present girls failed to do their homework.

**Calculation:**
\[ \text{Number of girls who failed to do homework} = 20\% \text{ of } 35 = \frac{20}{100} \times 35 = 7 \]

### Step 3: Calculate the number of girls who did the homework
Now, we can find out how many girls did complete their homework by subtracting the number of girls who failed from the total number of girls present.

**Calculation:**
\[ \text{Number of girls who did homework} = \text{Number of girls present} - \text{Number of girls who failed} = 35 - 7 = 28 \]

### Final Answer
The number of girls who did the homework is **28**.

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