Finding the Fourth Proportional to 13,142.02, 18,136.17 and 7,839.91

Step by Step Solution

1. Step 1: Write the proportion equation
   13,142.02 : 18,136.17 = 7,839.91 : x
2. Step 2: Convert to fraction form
   13,142.02/18,136.17 = 7,839.91/x
3. Step 3: Cross multiply
   13,142.02x = 18,136.17 × 7,839.91
4. Step 4: Simplify right side
   13,142.02x = 142,185,940.54
5. Step 5: Solve for x
   x = 142,185,940.54/13,142.02
6. Step 6: Final answer
   x = 10,819.18