Finding the Fourth Proportional to 12,321.12, 18,479.88 and 3,555

Step by Step Solution

1. Step 1: Write the proportion equation
   12,321.12 : 18,479.88 = 3,555 : x
2. Step 2: Convert to fraction form
   12,321.12/18,479.88 = 3,555/x
3. Step 3: Cross multiply
   12,321.12x = 18,479.88 × 3,555
4. Step 4: Simplify right side
   12,321.12x = 65,695,973.40
5. Step 5: Solve for x
   x = 65,695,973.40/12,321.12
6. Step 6: Final answer
   x = 5,331.98