Finding the Fourth Proportional to 2,515.59, 3,773.79 and 871.74

Step by Step Solution

1. Step 1: Write the proportion equation
   2,515.59 : 3,773.79 = 871.74 : x
2. Step 2: Convert to fraction form
   2,515.59/3,773.79 = 871.74/x
3. Step 3: Cross multiply
   2,515.59x = 3,773.79 × 871.74
4. Step 4: Simplify right side
   2,515.59x = 3,289,763.69
5. Step 5: Solve for x
   x = 3,289,763.69/2,515.59
6. Step 6: Final answer
   x = 1,307.75