Finding the Fourth Proportional to 10,663.74, 15,974.10 and 5,391.42

Step by Step Solution

1. Step 1: Write the proportion equation
   10,663.74 : 15,974.10 = 5,391.42 : x
2. Step 2: Convert to fraction form
   10,663.74/15,974.10 = 5,391.42/x
3. Step 3: Cross multiply
   10,663.74x = 15,974.10 × 5,391.42
4. Step 4: Simplify right side
   10,663.74x = 86,123,082.22
5. Step 5: Solve for x
   x = 86,123,082.22/10,663.74
6. Step 6: Final answer
   x = 8,076.25