Finding the Fourth Proportional to 2,820.27, 3,891.73 and 1,561.31

Step by Step Solution

1. Step 1: Write the proportion equation
   2,820.27 : 3,891.73 = 1,561.31 : x
2. Step 2: Convert to fraction form
   2,820.27/3,891.73 = 1,561.31/x
3. Step 3: Cross multiply
   2,820.27x = 3,891.73 × 1,561.31
4. Step 4: Simplify right side
   2,820.27x = 6,076,196.97
5. Step 5: Solve for x
   x = 6,076,196.97/2,820.27
6. Step 6: Final answer
   x = 2,154.47