Finding the Fourth Proportional to 9,913.10, 13,680.09 and 5,436.89

Step by Step Solution

1. Step 1: Write the proportion equation
   9,913.10 : 13,680.09 = 5,436.89 : x
2. Step 2: Convert to fraction form
   9,913.10/13,680.09 = 5,436.89/x
3. Step 3: Cross multiply
   9,913.10x = 13,680.09 × 5,436.89
4. Step 4: Simplify right side
   9,913.10x = 74,377,076.12
5. Step 5: Solve for x
   x = 74,377,076.12/9,913.10
6. Step 6: Final answer
   x = 7,502.91