Finding the Third Proportional to 2,139,678 and 4,616,409

Step by Step Solution

1. Step 1: Write the proportion equation
   2,139,678 : 4,616,409 = 4,616,409 : x
2. Step 2: Convert to fraction form
   2,139,678/4,616,409 = 4,616,409/x
3. Step 3: Cross multiply
   2,139,678x = 4,616,409 × 4,616,409
4. Step 4: Simplify right side
   2,139,678x = 21,311,232,055,281
5. Step 5: Solve for x
   x = 21,311,232,055,281/2,139,678
6. Step 6: Final answer
   x = 9,960,018.31