Finding the Fourth Proportional to 8,915.30, 13,386.78 and 8,520.83

Step by Step Solution

1. Step 1: Write the proportion equation
   8,915.30 : 13,386.78 = 8,520.83 : x
2. Step 2: Convert to fraction form
   8,915.30/13,386.78 = 8,520.83/x
3. Step 3: Cross multiply
   8,915.30x = 13,386.78 × 8,520.83
4. Step 4: Simplify right side
   8,915.30x = 114,066,476.63
5. Step 5: Solve for x
   x = 114,066,476.63/8,915.30
6. Step 6: Final answer
   x = 12,794.46