Finding the Third Proportional to 3,879,638 and 8,378,764

Step by Step Solution

1. Step 1: Write the proportion equation
   3,879,638 : 8,378,764 = 8,378,764 : x
2. Step 2: Convert to fraction form
   3,879,638/8,378,764 = 8,378,764/x
3. Step 3: Cross multiply
   3,879,638x = 8,378,764 × 8,378,764
4. Step 4: Simplify right side
   3,879,638x = 70,203,686,167,696
5. Step 5: Solve for x
   x = 70,203,686,167,696/3,879,638
6. Step 6: Final answer
   x = 18,095,421.83