Finding the Third Proportional to 315,426 and 691,919.25

Step by Step Solution

1. Step 1: Write the proportion equation
   315,426 : 691,919.25 = 691,919.25 : x
2. Step 2: Convert to fraction form
   315,426/691,919.25 = 691,919.25/x
3. Step 3: Cross multiply
   315,426x = 691,919.25 × 691,919.25
4. Step 4: Simplify right side
   315,426x = 478,752,248,520.56
5. Step 5: Solve for x
   x = 478,752,248,520.56/315,426
6. Step 6: Final answer
   x = 1,517,795.77