Finding the Fourth Proportional to 8,987.72, 13,478.94 and 3,143.24

Step by Step Solution

1. Step 1: Write the proportion equation
   8,987.72 : 13,478.94 = 3,143.24 : x
2. Step 2: Convert to fraction form
   8,987.72/13,478.94 = 3,143.24/x
3. Step 3: Cross multiply
   8,987.72x = 13,478.94 × 3,143.24
4. Step 4: Simplify right side
   8,987.72x = 42,367,543.37
5. Step 5: Solve for x
   x = 42,367,543.37/8,987.72
6. Step 6: Final answer
   x = 4,713.94