Finding the Fourth Proportional to 285,942.42, 428,916.72 and 86,264.55

Step by Step Solution

1. Step 1: Write the proportion equation
   285,942.42 : 428,916.72 = 86,264.55 : x
2. Step 2: Convert to fraction form
   285,942.42/428,916.72 = 86,264.55/x
3. Step 3: Cross multiply
   285,942.42x = 428,916.72 × 86,264.55
4. Step 4: Simplify right side
   285,942.42x = 37,000,307,838.28
5. Step 5: Solve for x
   x = 37,000,307,838.28/285,942.42
6. Step 6: Final answer
   x = 129,397.76