Finding the Fourth Proportional to 9,057.78, 12,493.20 and 5,521.14

Step by Step Solution

1. Step 1: Write the proportion equation
   9,057.78 : 12,493.20 = 5,521.14 : x
2. Step 2: Convert to fraction form
   9,057.78/12,493.20 = 5,521.14/x
3. Step 3: Cross multiply
   9,057.78x = 12,493.20 × 5,521.14
4. Step 4: Simplify right side
   9,057.78x = 68,976,706.25
5. Step 5: Solve for x
   x = 68,976,706.25/9,057.78
6. Step 6: Final answer
   x = 7,615.19