Finding the Fourth Proportional to 12,980.72, 19,468.92 and 5,187.44

Step by Step Solution

1. Step 1: Write the proportion equation
   12,980.72 : 19,468.92 = 5,187.44 : x
2. Step 2: Convert to fraction form
   12,980.72/19,468.92 = 5,187.44/x
3. Step 3: Cross multiply
   12,980.72x = 19,468.92 × 5,187.44
4. Step 4: Simplify right side
   12,980.72x = 100,993,854.36
5. Step 5: Solve for x
   x = 100,993,854.36/12,980.72
6. Step 6: Final answer
   x = 7,780.30