Finding the Fourth Proportional to 12,618.50, 17,287.42 and 12,145.56

Step by Step Solution

1. Step 1: Write the proportion equation
   12,618.50 : 17,287.42 = 12,145.56 : x
2. Step 2: Convert to fraction form
   12,618.50/17,287.42 = 12,145.56/x
3. Step 3: Cross multiply
   12,618.50x = 17,287.42 × 12,145.56
4. Step 4: Simplify right side
   12,618.50x = 209,965,366.49
5. Step 5: Solve for x
   x = 209,965,366.49/12,618.50
6. Step 6: Final answer
   x = 16,639.49