Finding the Fourth Proportional to 21,820.47, 30,093.98 and 13,422.39

Step by Step Solution

1. Step 1: Write the proportion equation
   21,820.47 : 30,093.98 = 13,422.39 : x
2. Step 2: Convert to fraction form
   21,820.47/30,093.98 = 13,422.39/x
3. Step 3: Cross multiply
   21,820.47x = 30,093.98 × 13,422.39
4. Step 4: Simplify right side
   21,820.47x = 403,933,069.10
5. Step 5: Solve for x
   x = 403,933,069.10/21,820.47
6. Step 6: Final answer
   x = 18,511.66