Finding the Fourth Proportional to 12,992.42, 19,355.72 and 12,365.48

Step by Step Solution

1. Step 1: Write the proportion equation
   12,992.42 : 19,355.72 = 12,365.48 : x
2. Step 2: Convert to fraction form
   12,992.42/19,355.72 = 12,365.48/x
3. Step 3: Cross multiply
   12,992.42x = 19,355.72 × 12,365.48
4. Step 4: Simplify right side
   12,992.42x = 239,342,768.55
5. Step 5: Solve for x
   x = 239,342,768.55/12,992.42
6. Step 6: Final answer
   x = 18,421.72