Finding the Third Proportional to 3,980.81 and 8,287.31

Step by Step Solution

1. Step 1: Write the proportion equation
   3,980.81 : 8,287.31 = 8,287.31 : x
2. Step 2: Convert to fraction form
   3,980.81/8,287.31 = 8,287.31/x
3. Step 3: Cross multiply
   3,980.81x = 8,287.31 × 8,287.31
4. Step 4: Simplify right side
   3,980.81x = 68,679,548.47
5. Step 5: Solve for x
   x = 68,679,548.47/3,980.81
6. Step 6: Final answer
   x = 17,252.65