Finding the Fourth Proportional to 9,907.12, 13,671.82 and 5,715.37

Step by Step Solution

1. Step 1: Write the proportion equation
   9,907.12 : 13,671.82 = 5,715.37 : x
2. Step 2: Convert to fraction form
   9,907.12/13,671.82 = 5,715.37/x
3. Step 3: Cross multiply
   9,907.12x = 13,671.82 × 5,715.37
4. Step 4: Simplify right side
   9,907.12x = 78,139,509.87
5. Step 5: Solve for x
   x = 78,139,509.87/9,907.12
6. Step 6: Final answer
   x = 7,887.21