Finding the Fourth Proportional to 2,520.20, 3,780.17 and 765.12

Step by Step Solution

1. Step 1: Write the proportion equation
   2,520.20 : 3,780.17 = 765.12 : x
2. Step 2: Convert to fraction form
   2,520.20/3,780.17 = 765.12/x
3. Step 3: Cross multiply
   2,520.20x = 3,780.17 × 765.12
4. Step 4: Simplify right side
   2,520.20x = 2,892,285.58
5. Step 5: Solve for x
   x = 2,892,285.58/2,520.20
6. Step 6: Final answer
   x = 1,147.64