Finding the Fourth Proportional to 2,185.72, 3,278.52 and 542.23

Step by Step Solution

1. Step 1: Write the proportion equation
   2,185.72 : 3,278.52 = 542.23 : x
2. Step 2: Convert to fraction form
   2,185.72/3,278.52 = 542.23/x
3. Step 3: Cross multiply
   2,185.72x = 3,278.52 × 542.23
4. Step 4: Simplify right side
   2,185.72x = 1,777,711.90
5. Step 5: Solve for x
   x = 1,777,711.90/2,185.72
6. Step 6: Final answer
   x = 813.33