Finding the Fourth Proportional to 9,199.72, 13,728.88 and 8,215.52

Step by Step Solution

1. Step 1: Write the proportion equation
   9,199.72 : 13,728.88 = 8,215.52 : x
2. Step 2: Convert to fraction form
   9,199.72/13,728.88 = 8,215.52/x
3. Step 3: Cross multiply
   9,199.72x = 13,728.88 × 8,215.52
4. Step 4: Simplify right side
   9,199.72x = 112,789,888.22
5. Step 5: Solve for x
   x = 112,789,888.22/9,199.72
6. Step 6: Final answer
   x = 12,260.14