Finding the Fourth Proportional to 677,684.31, 935,047.33 and 405,648.78

Step by Step Solution

1. Step 1: Write the proportion equation
   677,684.31 : 935,047.33 = 405,648.78 : x
2. Step 2: Convert to fraction form
   677,684.31/935,047.33 = 405,648.78/x
3. Step 3: Cross multiply
   677,684.31x = 935,047.33 × 405,648.78
4. Step 4: Simplify right side
   677,684.31x = 379,300,808,656.76
5. Step 5: Solve for x
   x = 379,300,808,656.76/677,684.31
6. Step 6: Final answer
   x = 559,701.33