Finding the Fourth Proportional to 21,106.17, 31,663.94 and 7,958.66

Step by Step Solution

1. Step 1: Write the proportion equation
   21,106.17 : 31,663.94 = 7,958.66 : x
2. Step 2: Convert to fraction form
   21,106.17/31,663.94 = 7,958.66/x
3. Step 3: Cross multiply
   21,106.17x = 31,663.94 × 7,958.66
4. Step 4: Simplify right side
   21,106.17x = 252,002,532.72
5. Step 5: Solve for x
   x = 252,002,532.72/21,106.17
6. Step 6: Final answer
   x = 11,939.76