Finding the Fourth Proportional to 9,907.80, 13,671.98 and 5,715.24

Step by Step Solution

1. Step 1: Write the proportion equation
   9,907.80 : 13,671.98 = 5,715.24 : x
2. Step 2: Convert to fraction form
   9,907.80/13,671.98 = 5,715.24/x
3. Step 3: Cross multiply
   9,907.80x = 13,671.98 × 5,715.24
4. Step 4: Simplify right side
   9,907.80x = 78,138,646.98
5. Step 5: Solve for x
   x = 78,138,646.98/9,907.80
6. Step 6: Final answer
   x = 7,886.58