Finding the Fourth Proportional to 21,919, 32,882.82 and 7,128.28

Step by Step Solution

1. Step 1: Write the proportion equation
   21,919 : 32,882.82 = 7,128.28 : x
2. Step 2: Convert to fraction form
   21,919/32,882.82 = 7,128.28/x
3. Step 3: Cross multiply
   21,919x = 32,882.82 × 7,128.28
4. Step 4: Simplify right side
   21,919x = 234,397,948.15
5. Step 5: Solve for x
   x = 234,397,948.15/21,919
6. Step 6: Final answer
   x = 10,693.82