Finding the Fourth Proportional to 21,799.91, 30,083.59 and 12,847.79

Step by Step Solution

1. Step 1: Write the proportion equation
   21,799.91 : 30,083.59 = 12,847.79 : x
2. Step 2: Convert to fraction form
   21,799.91/30,083.59 = 12,847.79/x
3. Step 3: Cross multiply
   21,799.91x = 30,083.59 × 12,847.79
4. Step 4: Simplify right side
   21,799.91x = 386,507,646.77
5. Step 5: Solve for x
   x = 386,507,646.77/21,799.91
6. Step 6: Final answer
   x = 17,729.78