Finding the Fourth Proportional to 9,099.72, 12,549.06 and 8,420.94

Step by Step Solution

1. Step 1: Write the proportion equation
   9,099.72 : 12,549.06 = 8,420.94 : x
2. Step 2: Convert to fraction form
   9,099.72/12,549.06 = 8,420.94/x
3. Step 3: Cross multiply
   9,099.72x = 12,549.06 × 8,420.94
4. Step 4: Simplify right side
   9,099.72x = 105,674,881.32
5. Step 5: Solve for x
   x = 105,674,881.32/9,099.72
6. Step 6: Final answer
   x = 11,612.98