Finding the Fourth Proportional to 9,915.17, 13,683.35 and 5,439.09

Step by Step Solution

1. Step 1: Write the proportion equation
   9,915.17 : 13,683.35 = 5,439.09 : x
2. Step 2: Convert to fraction form
   9,915.17/13,683.35 = 5,439.09/x
3. Step 3: Cross multiply
   9,915.17x = 13,683.35 × 5,439.09
4. Step 4: Simplify right side
   9,915.17x = 74,424,972.15
5. Step 5: Solve for x
   x = 74,424,972.15/9,915.17
6. Step 6: Final answer
   x = 7,506.17