Finding the Fourth Proportional to 9,369.56, 12,928.68 and 5,390.12

Step by Step Solution

1. Step 1: Write the proportion equation
   9,369.56 : 12,928.68 = 5,390.12 : x
2. Step 2: Convert to fraction form
   9,369.56/12,928.68 = 5,390.12/x
3. Step 3: Cross multiply
   9,369.56x = 12,928.68 × 5,390.12
4. Step 4: Simplify right side
   9,369.56x = 69,687,136.64
5. Step 5: Solve for x
   x = 69,687,136.64/9,369.56
6. Step 6: Final answer
   x = 7,437.61