Finding the Fourth Proportional to 9,978.93, 13,771.49 and 5,729.97

Step by Step Solution

1. Step 1: Write the proportion equation
   9,978.93 : 13,771.49 = 5,729.97 : x
2. Step 2: Convert to fraction form
   9,978.93/13,771.49 = 5,729.97/x
3. Step 3: Cross multiply
   9,978.93x = 13,771.49 × 5,729.97
4. Step 4: Simplify right side
   9,978.93x = 78,910,247.55
5. Step 5: Solve for x
   x = 78,910,247.55/9,978.93
6. Step 6: Final answer
   x = 7,907.69