Finding the Fourth Proportional to 12,921.12, 19,388.16 and 5,132.16

Step by Step Solution

1. Step 1: Write the proportion equation
   12,921.12 : 19,388.16 = 5,132.16 : x
2. Step 2: Convert to fraction form
   12,921.12/19,388.16 = 5,132.16/x
3. Step 3: Cross multiply
   12,921.12x = 19,388.16 × 5,132.16
4. Step 4: Simplify right side
   12,921.12x = 99,503,139.23
5. Step 5: Solve for x
   x = 99,503,139.23/12,921.12
6. Step 6: Final answer
   x = 7,700.81