Finding the Fourth Proportional to 22,390.78, 30,912.56 and 19,899.65

Step by Step Solution

1. Step 1: Write the proportion equation
   22,390.78 : 30,912.56 = 19,899.65 : x
2. Step 2: Convert to fraction form
   22,390.78/30,912.56 = 19,899.65/x
3. Step 3: Cross multiply
   22,390.78x = 30,912.56 × 19,899.65
4. Step 4: Simplify right side
   22,390.78x = 615,149,146.04
5. Step 5: Solve for x
   x = 615,149,146.04/22,390.78
6. Step 6: Final answer
   x = 27,473.32