Finding the Fourth Proportional to 9,978.32, 13,769.92 and 5,729.47

Step by Step Solution

1. Step 1: Write the proportion equation
   9,978.32 : 13,769.92 = 5,729.47 : x
2. Step 2: Convert to fraction form
   9,978.32/13,769.92 = 5,729.47/x
3. Step 3: Cross multiply
   9,978.32x = 13,769.92 × 5,729.47
4. Step 4: Simplify right side
   9,978.32x = 78,894,343.54
5. Step 5: Solve for x
   x = 78,894,343.54/9,978.32
6. Step 6: Final answer
   x = 7,906.58