Finding the Fourth Proportional to 9,915.46, 13,684.20 and 5,440.09

Step by Step Solution

1. Step 1: Write the proportion equation
   9,915.46 : 13,684.20 = 5,440.09 : x
2. Step 2: Convert to fraction form
   9,915.46/13,684.20 = 5,440.09/x
3. Step 3: Cross multiply
   9,915.46x = 13,684.20 × 5,440.09
4. Step 4: Simplify right side
   9,915.46x = 74,443,211.16
5. Step 5: Solve for x
   x = 74,443,211.16/9,915.46
6. Step 6: Final answer
   x = 7,507.80