Finding the Fourth Proportional to 12,111.80, 18,167.55 and 4,214.17

Step by Step Solution

1. Step 1: Write the proportion equation
   12,111.80 : 18,167.55 = 4,214.17 : x
2. Step 2: Convert to fraction form
   12,111.80/18,167.55 = 4,214.17/x
3. Step 3: Cross multiply
   12,111.80x = 18,167.55 × 4,214.17
4. Step 4: Simplify right side
   12,111.80x = 76,561,098.76
5. Step 5: Solve for x
   x = 76,561,098.76/12,111.80
6. Step 6: Final answer
   x = 6,321.20