Finding the Fourth Proportional to 20,901.72, 31,364.84 and 7,763.20

Step by Step Solution

1. Step 1: Write the proportion equation
   20,901.72 : 31,364.84 = 7,763.20 : x
2. Step 2: Convert to fraction form
   20,901.72/31,364.84 = 7,763.20/x
3. Step 3: Cross multiply
   20,901.72x = 31,364.84 × 7,763.20
4. Step 4: Simplify right side
   20,901.72x = 243,491,525.89
5. Step 5: Solve for x
   x = 243,491,525.89/20,901.72
6. Step 6: Final answer
   x = 11,649.35