Finding the Fourth Proportional to 2,380.86, 3,570.66 and 820.62

Step by Step Solution

1. Step 1: Write the proportion equation
   2,380.86 : 3,570.66 = 820.62 : x
2. Step 2: Convert to fraction form
   2,380.86/3,570.66 = 820.62/x
3. Step 3: Cross multiply
   2,380.86x = 3,570.66 × 820.62
4. Step 4: Simplify right side
   2,380.86x = 2,930,155.01
5. Step 5: Solve for x
   x = 2,930,155.01/2,380.86
6. Step 6: Final answer
   x = 1,230.71