Finding the Fourth Proportional to 1,818.86, 2,728.71 and 520.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,818.86 : 2,728.71 = 520.34 : x
2. Step 2: Convert to fraction form
   1,818.86/2,728.71 = 520.34/x
3. Step 3: Cross multiply
   1,818.86x = 2,728.71 × 520.34
4. Step 4: Simplify right side
   1,818.86x = 1,419,843.32
5. Step 5: Solve for x
   x = 1,419,843.32/1,818.86
6. Step 6: Final answer
   x = 780.62