Finding the Fourth Proportional to 9,358.56, 12,915.36 and 5,380.80

Step by Step Solution

1. Step 1: Write the proportion equation
   9,358.56 : 12,915.36 = 5,380.80 : x
2. Step 2: Convert to fraction form
   9,358.56/12,915.36 = 5,380.80/x
3. Step 3: Cross multiply
   9,358.56x = 12,915.36 × 5,380.80
4. Step 4: Simplify right side
   9,358.56x = 69,494,969.09
5. Step 5: Solve for x
   x = 69,494,969.09/9,358.56
6. Step 6: Final answer
   x = 7,425.82