Finding the Fourth Proportional to 21,016.39, 31,516.38 and 9,173.79

Step by Step Solution

1. Step 1: Write the proportion equation
   21,016.39 : 31,516.38 = 9,173.79 : x
2. Step 2: Convert to fraction form
   21,016.39/31,516.38 = 9,173.79/x
3. Step 3: Cross multiply
   21,016.39x = 31,516.38 × 9,173.79
4. Step 4: Simplify right side
   21,016.39x = 289,124,494.10
5. Step 5: Solve for x
   x = 289,124,494.10/21,016.39
6. Step 6: Final answer
   x = 13,757.10