Finding the Fourth Proportional to 2,380.52, 3,570.42 and 820.28

Step by Step Solution

1. Step 1: Write the proportion equation
   2,380.52 : 3,570.42 = 820.28 : x
2. Step 2: Convert to fraction form
   2,380.52/3,570.42 = 820.28/x
3. Step 3: Cross multiply
   2,380.52x = 3,570.42 × 820.28
4. Step 4: Simplify right side
   2,380.52x = 2,928,744.12
5. Step 5: Solve for x
   x = 2,928,744.12/2,380.52
6. Step 6: Final answer
   x = 1,230.30