Finding the Fourth Proportional to 2,520.81, 3,781.61 and 877.82

Step by Step Solution

1. Step 1: Write the proportion equation
   2,520.81 : 3,781.61 = 877.82 : x
2. Step 2: Convert to fraction form
   2,520.81/3,781.61 = 877.82/x
3. Step 3: Cross multiply
   2,520.81x = 3,781.61 × 877.82
4. Step 4: Simplify right side
   2,520.81x = 3,319,572.89
5. Step 5: Solve for x
   x = 3,319,572.89/2,520.81
6. Step 6: Final answer
   x = 1,316.87