Finding the Third Proportional to 3,998.56 and 8,458.50

Step by Step Solution

1. Step 1: Write the proportion equation
   3,998.56 : 8,458.50 = 8,458.50 : x
2. Step 2: Convert to fraction form
   3,998.56/8,458.50 = 8,458.50/x
3. Step 3: Cross multiply
   3,998.56x = 8,458.50 × 8,458.50
4. Step 4: Simplify right side
   3,998.56x = 71,546,222.25
5. Step 5: Solve for x
   x = 71,546,222.25/3,998.56
6. Step 6: Final answer
   x = 17,892.99