Finding the Fourth Proportional to 7,165.26, 9,887.58 and 3,978.50

Step by Step Solution

1. Step 1: Write the proportion equation
   7,165.26 : 9,887.58 = 3,978.50 : x
2. Step 2: Convert to fraction form
   7,165.26/9,887.58 = 3,978.50/x
3. Step 3: Cross multiply
   7,165.26x = 9,887.58 × 3,978.50
4. Step 4: Simplify right side
   7,165.26x = 39,337,687.59
5. Step 5: Solve for x
   x = 39,337,687.59/7,165.26
6. Step 6: Final answer
   x = 5,490.06