Finding the Fourth Proportional to 3,934.31, 5,428.89 and 2,255.25

Step by Step Solution

1. Step 1: Write the proportion equation
   3,934.31 : 5,428.89 = 2,255.25 : x
2. Step 2: Convert to fraction form
   3,934.31/5,428.89 = 2,255.25/x
3. Step 3: Cross multiply
   3,934.31x = 5,428.89 × 2,255.25
4. Step 4: Simplify right side
   3,934.31x = 12,243,504.17
5. Step 5: Solve for x
   x = 12,243,504.17/3,934.31
6. Step 6: Final answer
   x = 3,111.99