Finding the Fourth Proportional to 2,380.93, 3,571.89 and 820.87

Step by Step Solution

1. Step 1: Write the proportion equation
   2,380.93 : 3,571.89 = 820.87 : x
2. Step 2: Convert to fraction form
   2,380.93/3,571.89 = 820.87/x
3. Step 3: Cross multiply
   2,380.93x = 3,571.89 × 820.87
4. Step 4: Simplify right side
   2,380.93x = 2,932,057.34
5. Step 5: Solve for x
   x = 2,932,057.34/2,380.93
6. Step 6: Final answer
   x = 1,231.48