Finding the Fourth Proportional to 12,879.50, 19,312.15 and 3,992.37

Step by Step Solution

1. Step 1: Write the proportion equation
   12,879.50 : 19,312.15 = 3,992.37 : x
2. Step 2: Convert to fraction form
   12,879.50/19,312.15 = 3,992.37/x
3. Step 3: Cross multiply
   12,879.50x = 19,312.15 × 3,992.37
4. Step 4: Simplify right side
   12,879.50x = 77,101,131.77
5. Step 5: Solve for x
   x = 77,101,131.77/12,879.50
6. Step 6: Final answer
   x = 5,986.35