Finding the Fourth Proportional to 21,258.82, 31,886.94 and 7,929.25

Step by Step Solution

1. Step 1: Write the proportion equation
   21,258.82 : 31,886.94 = 7,929.25 : x
2. Step 2: Convert to fraction form
   21,258.82/31,886.94 = 7,929.25/x
3. Step 3: Cross multiply
   21,258.82x = 31,886.94 × 7,929.25
4. Step 4: Simplify right side
   21,258.82x = 252,839,401.87
5. Step 5: Solve for x
   x = 252,839,401.87/21,258.82
6. Step 6: Final answer
   x = 11,893.39