Finding the Fourth Proportional to 21,308.05, 31,969.86 and 9,915.41

Step by Step Solution

1. Step 1: Write the proportion equation
   21,308.05 : 31,969.86 = 9,915.41 : x
2. Step 2: Convert to fraction form
   21,308.05/31,969.86 = 9,915.41/x
3. Step 3: Cross multiply
   21,308.05x = 31,969.86 × 9,915.41
4. Step 4: Simplify right side
   21,308.05x = 316,994,134.48
5. Step 5: Solve for x
   x = 316,994,134.48/21,308.05
6. Step 6: Final answer
   x = 14,876.73