Finding the Third Proportional to 3,989.25 and 8,564.06

Step by Step Solution

1. Step 1: Write the proportion equation
   3,989.25 : 8,564.06 = 8,564.06 : x
2. Step 2: Convert to fraction form
   3,989.25/8,564.06 = 8,564.06/x
3. Step 3: Cross multiply
   3,989.25x = 8,564.06 × 8,564.06
4. Step 4: Simplify right side
   3,989.25x = 73,343,166.50
5. Step 5: Solve for x
   x = 73,343,166.50/3,989.25
6. Step 6: Final answer
   x = 18,385.20