Finding the Fourth Proportional to 15,494.96, 21,382.17 and 8,421.33

Step by Step Solution

1. Step 1: Write the proportion equation
   15,494.96 : 21,382.17 = 8,421.33 : x
2. Step 2: Convert to fraction form
   15,494.96/21,382.17 = 8,421.33/x
3. Step 3: Cross multiply
   15,494.96x = 21,382.17 × 8,421.33
4. Step 4: Simplify right side
   15,494.96x = 180,066,309.69
5. Step 5: Solve for x
   x = 180,066,309.69/15,494.96
6. Step 6: Final answer
   x = 11,620.96