Finding the Fourth Proportional to 21,728.43, 32,581.62 and 10,618.47

Step by Step Solution

1. Step 1: Write the proportion equation
   21,728.43 : 32,581.62 = 10,618.47 : x
2. Step 2: Convert to fraction form
   21,728.43/32,581.62 = 10,618.47/x
3. Step 3: Cross multiply
   21,728.43x = 32,581.62 × 10,618.47
4. Step 4: Simplify right side
   21,728.43x = 345,966,954.52
5. Step 5: Solve for x
   x = 345,966,954.52/21,728.43
6. Step 6: Final answer
   x = 15,922.32