Finding the Third Proportional to 12,987 and 18,085.50

Step by Step Solution

1. Step 1: Write the proportion equation
   12,987 : 18,085.50 = 18,085.50 : x
2. Step 2: Convert to fraction form
   12,987/18,085.50 = 18,085.50/x
3. Step 3: Cross multiply
   12,987x = 18,085.50 × 18,085.50
4. Step 4: Simplify right side
   12,987x = 327,085,310.25
5. Step 5: Solve for x
   x = 327,085,310.25/12,987
6. Step 6: Final answer
   x = 25,185.59