Finding the Fourth Proportional to 8,136.82, 12,215.31 and 8,099.38

Step by Step Solution

1. Step 1: Write the proportion equation
   8,136.82 : 12,215.31 = 8,099.38 : x
2. Step 2: Convert to fraction form
   8,136.82/12,215.31 = 8,099.38/x
3. Step 3: Cross multiply
   8,136.82x = 12,215.31 × 8,099.38
4. Step 4: Simplify right side
   8,136.82x = 98,936,437.51
5. Step 5: Solve for x
   x = 98,936,437.51/8,136.82
6. Step 6: Final answer
   x = 12,159.10