Finding the Fourth Proportional to 12,111.81, 18,167.20 and 4,216.12

Step by Step Solution

1. Step 1: Write the proportion equation
   12,111.81 : 18,167.20 = 4,216.12 : x
2. Step 2: Convert to fraction form
   12,111.81/18,167.20 = 4,216.12/x
3. Step 3: Cross multiply
   12,111.81x = 18,167.20 × 4,216.12
4. Step 4: Simplify right side
   12,111.81x = 76,595,095.26
5. Step 5: Solve for x
   x = 76,595,095.26/12,111.81
6. Step 6: Final answer
   x = 6,324.00