Finding the Fourth Proportional to 21,981.72, 32,952.60 and 8,121

Step by Step Solution

1. Step 1: Write the proportion equation
   21,981.72 : 32,952.60 = 8,121 : x
2. Step 2: Convert to fraction form
   21,981.72/32,952.60 = 8,121/x
3. Step 3: Cross multiply
   21,981.72x = 32,952.60 × 8,121
4. Step 4: Simplify right side
   21,981.72x = 267,608,064.60
5. Step 5: Solve for x
   x = 267,608,064.60/21,981.72
6. Step 6: Final answer
   x = 12,174.12