Finding the Fourth Proportional to 9,145.20, 12,620.04 and 5,167.20

Step by Step Solution

1. Step 1: Write the proportion equation
   9,145.20 : 12,620.04 = 5,167.20 : x
2. Step 2: Convert to fraction form
   9,145.20/12,620.04 = 5,167.20/x
3. Step 3: Cross multiply
   9,145.20x = 12,620.04 × 5,167.20
4. Step 4: Simplify right side
   9,145.20x = 65,210,270.69
5. Step 5: Solve for x
   x = 65,210,270.69/9,145.20
6. Step 6: Final answer
   x = 7,130.55