Finding the Fourth Proportional to 2,815.47, 4,221.59 and 867.15

Step by Step Solution

1. Step 1: Write the proportion equation
   2,815.47 : 4,221.59 = 867.15 : x
2. Step 2: Convert to fraction form
   2,815.47/4,221.59 = 867.15/x
3. Step 3: Cross multiply
   2,815.47x = 4,221.59 × 867.15
4. Step 4: Simplify right side
   2,815.47x = 3,660,747.43
5. Step 5: Solve for x
   x = 3,660,747.43/2,815.47
6. Step 6: Final answer
   x = 1,300.23