Finding the Fourth Proportional to 59,802.78, 81,930.20 and 57,560.70

Step by Step Solution

1. Step 1: Write the proportion equation
   59,802.78 : 81,930.20 = 57,560.70 : x
2. Step 2: Convert to fraction form
   59,802.78/81,930.20 = 57,560.70/x
3. Step 3: Cross multiply
   59,802.78x = 81,930.20 × 57,560.70
4. Step 4: Simplify right side
   59,802.78x = 4,715,959,375.34
5. Step 5: Solve for x
   x = 4,715,959,375.34/59,802.78
6. Step 6: Final answer
   x = 78,858.53