The first second and fourth terms of a proportion are 36, 81 and 63 respectively. Find the third term.

Answer

To find the third term of the proportion where the first, second, and fourth terms are given as 36, 81, and 63 respectively, we can follow these steps:

### Step-by-Step Solution:

1. **Set Up the Proportion**:
We know that in a proportion, the relationship can be expressed as:
\[ \frac{\text{First Term}}{\text{Second Term}} = \frac{\text{Third Term}}{\text{Fourth Term}} \]
Here, we can substitute the known values:
\[ \frac{36}{81} = \frac{x}{63} \]
where \( x \) is the third term we need to find.

2. **Cross Multiply**:
To eliminate the fractions, we cross multiply:
\[ 36 \times 63 = x \times 81 \]

3. **Calculate \( 36 \times 63 \)**:
Now, we calculate the left side:
\[ 36 \times 63 = 2268 \]

4. **Set Up the Equation**:
Now we have:
\[ 2268 = 81x \]

5. **Solve for \( x \)**:
To find \( x \), divide both sides by 81:
\[ x = \frac{2268}{81} \]

6. **Perform the Division**:
Now, we perform the division:
\[ x = 28 \]

### Final Answer:
The third term is \( x = 28 \).

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