Finding the Fourth Proportional to 13,136.91, 18,128.77 and 7,168.69

Step by Step Solution

1. Step 1: Write the proportion equation
   13,136.91 : 18,128.77 = 7,168.69 : x
2. Step 2: Convert to fraction form
   13,136.91/18,128.77 = 7,168.69/x
3. Step 3: Cross multiply
   13,136.91x = 18,128.77 × 7,168.69
4. Step 4: Simplify right side
   13,136.91x = 129,959,532.21
5. Step 5: Solve for x
   x = 129,959,532.21/13,136.91
6. Step 6: Final answer
   x = 9,892.70