Finding the Fourth Proportional to 3,871.89, 5,802.17 and 1,920.20

Step by Step Solution

1. Step 1: Write the proportion equation
   3,871.89 : 5,802.17 = 1,920.20 : x
2. Step 2: Convert to fraction form
   3,871.89/5,802.17 = 1,920.20/x
3. Step 3: Cross multiply
   3,871.89x = 5,802.17 × 1,920.20
4. Step 4: Simplify right side
   3,871.89x = 11,141,288.22
5. Step 5: Solve for x
   x = 11,141,288.22/3,871.89
6. Step 6: Final answer
   x = 2,877.48