Finding the Fourth Proportional to 21,971.88, 30,320.76 and 12,540.24

Step by Step Solution

1. Step 1: Write the proportion equation
   21,971.88 : 30,320.76 = 12,540.24 : x
2. Step 2: Convert to fraction form
   21,971.88/30,320.76 = 12,540.24/x
3. Step 3: Cross multiply
   21,971.88x = 30,320.76 × 12,540.24
4. Step 4: Simplify right side
   21,971.88x = 380,229,607.38
5. Step 5: Solve for x
   x = 380,229,607.38/21,971.88
6. Step 6: Final answer
   x = 17,305.28