Finding the Fourth Proportional to 2,520.81, 3,780.71 and 877.43

Step by Step Solution

1. Step 1: Write the proportion equation
   2,520.81 : 3,780.71 = 877.43 : x
2. Step 2: Convert to fraction form
   2,520.81/3,780.71 = 877.43/x
3. Step 3: Cross multiply
   2,520.81x = 3,780.71 × 877.43
4. Step 4: Simplify right side
   2,520.81x = 3,317,308.38
5. Step 5: Solve for x
   x = 3,317,308.38/2,520.81
6. Step 6: Final answer
   x = 1,315.97