Finding the Third Proportional to 3,978 and 8,581.50

Step by Step Solution

1. Step 1: Write the proportion equation
   3,978 : 8,581.50 = 8,581.50 : x
2. Step 2: Convert to fraction form
   3,978/8,581.50 = 8,581.50/x
3. Step 3: Cross multiply
   3,978x = 8,581.50 × 8,581.50
4. Step 4: Simplify right side
   3,978x = 73,642,142.25
5. Step 5: Solve for x
   x = 73,642,142.25/3,978
6. Step 6: Final answer
   x = 18,512.35