Finding the Third Proportional to 3,990,621 and 8,727,738

Step by Step Solution

1. Step 1: Write the proportion equation
   3,990,621 : 8,727,738 = 8,727,738 : x
2. Step 2: Convert to fraction form
   3,990,621/8,727,738 = 8,727,738/x
3. Step 3: Cross multiply
   3,990,621x = 8,727,738 × 8,727,738
4. Step 4: Simplify right side
   3,990,621x = 76,173,410,596,644
5. Step 5: Solve for x
   x = 76,173,410,596,644/3,990,621
6. Step 6: Final answer
   x = 19,088,109.49