Finding the Fourth Proportional to 9,179.31, 12,666.42 and 5,199.57

Step by Step Solution

1. Step 1: Write the proportion equation
   9,179.31 : 12,666.42 = 5,199.57 : x
2. Step 2: Convert to fraction form
   9,179.31/12,666.42 = 5,199.57/x
3. Step 3: Cross multiply
   9,179.31x = 12,666.42 × 5,199.57
4. Step 4: Simplify right side
   9,179.31x = 65,859,937.44
5. Step 5: Solve for x
   x = 65,859,937.44/9,179.31
6. Step 6: Final answer
   x = 7,174.82