Finding the Fourth Proportional to 677,926.15, 935,976.35 and 420,076.72

Step by Step Solution

1. Step 1: Write the proportion equation
   677,926.15 : 935,976.35 = 420,076.72 : x
2. Step 2: Convert to fraction form
   677,926.15/935,976.35 = 420,076.72/x
3. Step 3: Cross multiply
   677,926.15x = 935,976.35 × 420,076.72
4. Step 4: Simplify right side
   677,926.15x = 393,181,875,105.57
5. Step 5: Solve for x
   x = 393,181,875,105.57/677,926.15
6. Step 6: Final answer
   x = 579,977.44