Finding the Third Proportional to 3,899,434 and 8,415,424

Step by Step Solution

1. Step 1: Write the proportion equation
   3,899,434 : 8,415,424 = 8,415,424 : x
2. Step 2: Convert to fraction form
   3,899,434/8,415,424 = 8,415,424/x
3. Step 3: Cross multiply
   3,899,434x = 8,415,424 × 8,415,424
4. Step 4: Simplify right side
   3,899,434x = 70,819,361,099,776
5. Step 5: Solve for x
   x = 70,819,361,099,776/3,899,434
6. Step 6: Final answer
   x = 18,161,446.28