Finding the Fourth Proportional to 2,820.61, 3,892.43 and 1,578.61

Step by Step Solution

1. Step 1: Write the proportion equation
   2,820.61 : 3,892.43 = 1,578.61 : x
2. Step 2: Convert to fraction form
   2,820.61/3,892.43 = 1,578.61/x
3. Step 3: Cross multiply
   2,820.61x = 3,892.43 × 1,578.61
4. Step 4: Simplify right side
   2,820.61x = 6,144,601.57
5. Step 5: Solve for x
   x = 6,144,601.57/2,820.61
6. Step 6: Final answer
   x = 2,178.47