Finding the Fourth Proportional to 21,815.72, 30,105.80 and 12,384.44

Step by Step Solution

1. Step 1: Write the proportion equation
   21,815.72 : 30,105.80 = 12,384.44 : x
2. Step 2: Convert to fraction form
   21,815.72/30,105.80 = 12,384.44/x
3. Step 3: Cross multiply
   21,815.72x = 30,105.80 × 12,384.44
4. Step 4: Simplify right side
   21,815.72x = 372,843,473.75
5. Step 5: Solve for x
   x = 372,843,473.75/21,815.72
6. Step 6: Final answer
   x = 17,090.59