Finding the Fourth Proportional to 12,309.39, 18,459.50 and 3,987.23

Step by Step Solution

1. Step 1: Write the proportion equation
   12,309.39 : 18,459.50 = 3,987.23 : x
2. Step 2: Convert to fraction form
   12,309.39/18,459.50 = 3,987.23/x
3. Step 3: Cross multiply
   12,309.39x = 18,459.50 × 3,987.23
4. Step 4: Simplify right side
   12,309.39x = 73,602,159.95
5. Step 5: Solve for x
   x = 73,602,159.95/12,309.39
6. Step 6: Final answer
   x = 5,979.35