Finding the Fourth Proportional to 20,566.55, 30,843.69 and 8,720.12

Step by Step Solution

1. Step 1: Write the proportion equation
   20,566.55 : 30,843.69 = 8,720.12 : x
2. Step 2: Convert to fraction form
   20,566.55/30,843.69 = 8,720.12/x
3. Step 3: Cross multiply
   20,566.55x = 30,843.69 × 8,720.12
4. Step 4: Simplify right side
   20,566.55x = 268,960,722.45
5. Step 5: Solve for x
   x = 268,960,722.45/20,566.55
6. Step 6: Final answer
   x = 13,077.58