Finding the Fourth Proportional to 20,564.99, 30,859.82 and 8,878.20

Step by Step Solution

1. Step 1: Write the proportion equation
   20,564.99 : 30,859.82 = 8,878.20 : x
2. Step 2: Convert to fraction form
   20,564.99/30,859.82 = 8,878.20/x
3. Step 3: Cross multiply
   20,564.99x = 30,859.82 × 8,878.20
4. Step 4: Simplify right side
   20,564.99x = 273,979,521.82
5. Step 5: Solve for x
   x = 273,979,521.82/20,564.99
6. Step 6: Final answer
   x = 13,322.62