Finding the Fourth Proportional to 212,414.73, 318,622.91 and 86,057.34

Step by Step Solution

1. Step 1: Write the proportion equation
   212,414.73 : 318,622.91 = 86,057.34 : x
2. Step 2: Convert to fraction form
   212,414.73/318,622.91 = 86,057.34/x
3. Step 3: Cross multiply
   212,414.73x = 318,622.91 × 86,057.34
4. Step 4: Simplify right side
   212,414.73x = 27,419,839,667.37
5. Step 5: Solve for x
   x = 27,419,839,667.37/212,414.73
6. Step 6: Final answer
   x = 129,086.34