Finding the Fourth Proportional to 9,191.99, 12,684.89 and 5,415.12

Step by Step Solution

1. Step 1: Write the proportion equation
   9,191.99 : 12,684.89 = 5,415.12 : x
2. Step 2: Convert to fraction form
   9,191.99/12,684.89 = 5,415.12/x
3. Step 3: Cross multiply
   9,191.99x = 12,684.89 × 5,415.12
4. Step 4: Simplify right side
   9,191.99x = 68,690,174.46
5. Step 5: Solve for x
   x = 68,690,174.46/9,191.99
6. Step 6: Final answer
   x = 7,472.83