Finding the Third Proportional to 3,992,656 and 8,657,912

Step by Step Solution

1. Step 1: Write the proportion equation
   3,992,656 : 8,657,912 = 8,657,912 : x
2. Step 2: Convert to fraction form
   3,992,656/8,657,912 = 8,657,912/x
3. Step 3: Cross multiply
   3,992,656x = 8,657,912 × 8,657,912
4. Step 4: Simplify right side
   3,992,656x = 74,959,440,199,744
5. Step 5: Solve for x
   x = 74,959,440,199,744/3,992,656
6. Step 6: Final answer
   x = 18,774,329.72