Finding the Third Proportional to 3,940,428 and 8,509,560

Step by Step Solution

1. Step 1: Write the proportion equation
   3,940,428 : 8,509,560 = 8,509,560 : x
2. Step 2: Convert to fraction form
   3,940,428/8,509,560 = 8,509,560/x
3. Step 3: Cross multiply
   3,940,428x = 8,509,560 × 8,509,560
4. Step 4: Simplify right side
   3,940,428x = 72,412,611,393,600
5. Step 5: Solve for x
   x = 72,412,611,393,600/3,940,428
6. Step 6: Final answer
   x = 18,376,839.11