Finding the Fourth Proportional to 20,128.58, 30,184.43 and 7,641.72

Step by Step Solution

1. Step 1: Write the proportion equation
   20,128.58 : 30,184.43 = 7,641.72 : x
2. Step 2: Convert to fraction form
   20,128.58/30,184.43 = 7,641.72/x
3. Step 3: Cross multiply
   20,128.58x = 30,184.43 × 7,641.72
4. Step 4: Simplify right side
   20,128.58x = 230,660,924.21
5. Step 5: Solve for x
   x = 230,660,924.21/20,128.58
6. Step 6: Final answer
   x = 11,459.37