Finding the Fourth Proportional to 21,810.70, 30,098.91 and 12,379.42

Step by Step Solution

1. Step 1: Write the proportion equation
   21,810.70 : 30,098.91 = 12,379.42 : x
2. Step 2: Convert to fraction form
   21,810.70/30,098.91 = 12,379.42/x
3. Step 3: Cross multiply
   21,810.70x = 30,098.91 × 12,379.42
4. Step 4: Simplify right side
   21,810.70x = 372,607,048.43
5. Step 5: Solve for x
   x = 372,607,048.43/21,810.70
6. Step 6: Final answer
   x = 17,083.68