Finding the Fourth Proportional to 21,759.75, 30,031.29 and 12,808.08

Step by Step Solution

1. Step 1: Write the proportion equation
   21,759.75 : 30,031.29 = 12,808.08 : x
2. Step 2: Convert to fraction form
   21,759.75/30,031.29 = 12,808.08/x
3. Step 3: Cross multiply
   21,759.75x = 30,031.29 × 12,808.08
4. Step 4: Simplify right side
   21,759.75x = 384,643,164.82
5. Step 5: Solve for x
   x = 384,643,164.82/21,759.75
6. Step 6: Final answer
   x = 17,676.82