Finding the Fourth Proportional to 20,564.76, 30,775.86 and 12,663.76

Step by Step Solution

1. Step 1: Write the proportion equation
   20,564.76 : 30,775.86 = 12,663.76 : x
2. Step 2: Convert to fraction form
   20,564.76/30,775.86 = 12,663.76/x
3. Step 3: Cross multiply
   20,564.76x = 30,775.86 × 12,663.76
4. Step 4: Simplify right side
   20,564.76x = 389,738,104.83
5. Step 5: Solve for x
   x = 389,738,104.83/20,564.76
6. Step 6: Final answer
   x = 18,951.75