Finding the Fourth Proportional to 13,142.64, 18,136.86 and 8,426.91

Step by Step Solution

1. Step 1: Write the proportion equation
   13,142.64 : 18,136.86 = 8,426.91 : x
2. Step 2: Convert to fraction form
   13,142.64/18,136.86 = 8,426.91/x
3. Step 3: Cross multiply
   13,142.64x = 18,136.86 × 8,426.91
4. Step 4: Simplify right side
   13,142.64x = 152,837,686.90
5. Step 5: Solve for x
   x = 152,837,686.90/13,142.64
6. Step 6: Final answer
   x = 11,629.15