Finding the Fourth Proportional to 39,978.18, 55,165.05 and 22,071.78

Step by Step Solution

1. Step 1: Write the proportion equation
   39,978.18 : 55,165.05 = 22,071.78 : x
2. Step 2: Convert to fraction form
   39,978.18/55,165.05 = 22,071.78/x
3. Step 3: Cross multiply
   39,978.18x = 55,165.05 × 22,071.78
4. Step 4: Simplify right side
   39,978.18x = 1,217,590,847.29
5. Step 5: Solve for x
   x = 1,217,590,847.29/39,978.18
6. Step 6: Final answer
   x = 30,456.39