Finding the Fourth Proportional to 13,396.56, 18,487.47 and 7,428.48

Step by Step Solution

1. Step 1: Write the proportion equation
   13,396.56 : 18,487.47 = 7,428.48 : x
2. Step 2: Convert to fraction form
   13,396.56/18,487.47 = 7,428.48/x
3. Step 3: Cross multiply
   13,396.56x = 18,487.47 × 7,428.48
4. Step 4: Simplify right side
   13,396.56x = 137,333,801.15
5. Step 5: Solve for x
   x = 137,333,801.15/13,396.56
6. Step 6: Final answer
   x = 10,251.42