Finding the Fourth Proportional to 22,409.14, 30,922.80 and 12,978.31

Step by Step Solution

1. Step 1: Write the proportion equation
   22,409.14 : 30,922.80 = 12,978.31 : x
2. Step 2: Convert to fraction form
   22,409.14/30,922.80 = 12,978.31/x
3. Step 3: Cross multiply
   22,409.14x = 30,922.80 × 12,978.31
4. Step 4: Simplify right side
   22,409.14x = 401,325,684.47
5. Step 5: Solve for x
   x = 401,325,684.47/22,409.14
6. Step 6: Final answer
   x = 17,909.02