Finding the Fourth Proportional to 12,077.80, 18,105.90 and 7,919.80

Step by Step Solution

1. Step 1: Write the proportion equation
   12,077.80 : 18,105.90 = 7,919.80 : x
2. Step 2: Convert to fraction form
   12,077.80/18,105.90 = 7,919.80/x
3. Step 3: Cross multiply
   12,077.80x = 18,105.90 × 7,919.80
4. Step 4: Simplify right side
   12,077.80x = 143,395,106.82
5. Step 5: Solve for x
   x = 143,395,106.82/12,077.80
6. Step 6: Final answer
   x = 11,872.62