Finding the Fourth Proportional to 13,142.18, 18,136.16 and 7,173.86

Step by Step Solution

1. Step 1: Write the proportion equation
   13,142.18 : 18,136.16 = 7,173.86 : x
2. Step 2: Convert to fraction form
   13,142.18/18,136.16 = 7,173.86/x
3. Step 3: Cross multiply
   13,142.18x = 18,136.16 × 7,173.86
4. Step 4: Simplify right side
   13,142.18x = 130,106,190.93
5. Step 5: Solve for x
   x = 130,106,190.93/13,142.18
6. Step 6: Final answer
   x = 9,899.89