Finding the Fourth Proportional to 9,864.20, 13,612.41 and 5,387.99

Step by Step Solution

1. Step 1: Write the proportion equation
   9,864.20 : 13,612.41 = 5,387.99 : x
2. Step 2: Convert to fraction form
   9,864.20/13,612.41 = 5,387.99/x
3. Step 3: Cross multiply
   9,864.20x = 13,612.41 × 5,387.99
4. Step 4: Simplify right side
   9,864.20x = 73,343,460.89
5. Step 5: Solve for x
   x = 73,343,460.89/9,864.20
6. Step 6: Final answer
   x = 7,435.32