Finding the Fourth Proportional to 10,355.94, 14,291.28 and 5,640.21

Step by Step Solution

1. Step 1: Write the proportion equation
   10,355.94 : 14,291.28 = 5,640.21 : x
2. Step 2: Convert to fraction form
   10,355.94/14,291.28 = 5,640.21/x
3. Step 3: Cross multiply
   10,355.94x = 14,291.28 × 5,640.21
4. Step 4: Simplify right side
   10,355.94x = 80,605,820.37
5. Step 5: Solve for x
   x = 80,605,820.37/10,355.94
6. Step 6: Final answer
   x = 7,783.53