Finding the Fourth Proportional to 385,300.80, 531,693.72 and 215,502.12

Step by Step Solution

1. Step 1: Write the proportion equation
   385,300.80 : 531,693.72 = 215,502.12 : x
2. Step 2: Convert to fraction form
   385,300.80/531,693.72 = 215,502.12/x
3. Step 3: Cross multiply
   385,300.80x = 531,693.72 × 215,502.12
4. Step 4: Simplify right side
   385,300.80x = 114,581,123,850.69
5. Step 5: Solve for x
   x = 114,581,123,850.69/385,300.80
6. Step 6: Final answer
   x = 297,380.97