Finding the Fourth Proportional to 12,213.50, 18,320.34 and 2,979.50

Step by Step Solution

1. Step 1: Write the proportion equation
   12,213.50 : 18,320.34 = 2,979.50 : x
2. Step 2: Convert to fraction form
   12,213.50/18,320.34 = 2,979.50/x
3. Step 3: Cross multiply
   12,213.50x = 18,320.34 × 2,979.50
4. Step 4: Simplify right side
   12,213.50x = 54,585,453.03
5. Step 5: Solve for x
   x = 54,585,453.03/12,213.50
6. Step 6: Final answer
   x = 4,469.27