Finding the Fourth Proportional to 21,868.55, 30,173.40 and 12,442.31

Step by Step Solution

1. Step 1: Write the proportion equation
   21,868.55 : 30,173.40 = 12,442.31 : x
2. Step 2: Convert to fraction form
   21,868.55/30,173.40 = 12,442.31/x
3. Step 3: Cross multiply
   21,868.55x = 30,173.40 × 12,442.31
4. Step 4: Simplify right side
   21,868.55x = 375,426,796.55
5. Step 5: Solve for x
   x = 375,426,796.55/21,868.55
6. Step 6: Final answer
   x = 17,167.43