Finding the Fourth Proportional to 10,421.71, 14,388.66 and 9,300.73

Step by Step Solution

1. Step 1: Write the proportion equation
   10,421.71 : 14,388.66 = 9,300.73 : x
2. Step 2: Convert to fraction form
   10,421.71/14,388.66 = 9,300.73/x
3. Step 3: Cross multiply
   10,421.71x = 14,388.66 × 9,300.73
4. Step 4: Simplify right side
   10,421.71x = 133,825,041.72
5. Step 5: Solve for x
   x = 133,825,041.72/10,421.71
6. Step 6: Final answer
   x = 12,840.99