Finding the Fourth Proportional to 12,215.60, 18,321.81 and 5,194.31

Step by Step Solution

1. Step 1: Write the proportion equation
   12,215.60 : 18,321.81 = 5,194.31 : x
2. Step 2: Convert to fraction form
   12,215.60/18,321.81 = 5,194.31/x
3. Step 3: Cross multiply
   12,215.60x = 18,321.81 × 5,194.31
4. Step 4: Simplify right side
   12,215.60x = 95,169,069.29
5. Step 5: Solve for x
   x = 95,169,069.29/12,215.60
6. Step 6: Final answer
   x = 7,790.78