Finding the Fourth Proportional to 2,143.47, 3,215.34 and 827.85

Step by Step Solution

1. Step 1: Write the proportion equation
   2,143.47 : 3,215.34 = 827.85 : x
2. Step 2: Convert to fraction form
   2,143.47/3,215.34 = 827.85/x
3. Step 3: Cross multiply
   2,143.47x = 3,215.34 × 827.85
4. Step 4: Simplify right side
   2,143.47x = 2,661,819.22
5. Step 5: Solve for x
   x = 2,661,819.22/2,143.47
6. Step 6: Final answer
   x = 1,241.83