Finding the Third Proportional to 315,426 and 691,918.50

Step by Step Solution

1. Step 1: Write the proportion equation
   315,426 : 691,918.50 = 691,918.50 : x
2. Step 2: Convert to fraction form
   315,426/691,918.50 = 691,918.50/x
3. Step 3: Cross multiply
   315,426x = 691,918.50 × 691,918.50
4. Step 4: Simplify right side
   315,426x = 478,751,210,642.25
5. Step 5: Solve for x
   x = 478,751,210,642.25/315,426
6. Step 6: Final answer
   x = 1,517,792.48