Finding the Fourth Proportional to 142,815.57, 212,946.53 and 138,892.05

Step by Step Solution

1. Step 1: Write the proportion equation
   142,815.57 : 212,946.53 = 138,892.05 : x
2. Step 2: Convert to fraction form
   142,815.57/212,946.53 = 138,892.05/x
3. Step 3: Cross multiply
   142,815.57x = 212,946.53 × 138,892.05
4. Step 4: Simplify right side
   142,815.57x = 29,576,580,092.09
5. Step 5: Solve for x
   x = 29,576,580,092.09/142,815.57
6. Step 6: Final answer
   x = 207,096.33