Finding the Fourth Proportional to 10,420.27, 14,379.88 and 5,640.12

Step by Step Solution

1. Step 1: Write the proportion equation
   10,420.27 : 14,379.88 = 5,640.12 : x
2. Step 2: Convert to fraction form
   10,420.27/14,379.88 = 5,640.12/x
3. Step 3: Cross multiply
   10,420.27x = 14,379.88 × 5,640.12
4. Step 4: Simplify right side
   10,420.27x = 81,104,248.79
5. Step 5: Solve for x
   x = 81,104,248.79/10,420.27
6. Step 6: Final answer
   x = 7,783.32