Finding the Third Proportional to 4,138.31 and 8,379.56

Step by Step Solution

1. Step 1: Write the proportion equation
   4,138.31 : 8,379.56 = 8,379.56 : x
2. Step 2: Convert to fraction form
   4,138.31/8,379.56 = 8,379.56/x
3. Step 3: Cross multiply
   4,138.31x = 8,379.56 × 8,379.56
4. Step 4: Simplify right side
   4,138.31x = 70,217,067.69
5. Step 5: Solve for x
   x = 70,217,067.69/4,138.31
6. Step 6: Final answer
   x = 16,967.56