Finding the Third Proportional to 68,789.75 and 91,728.25

Step by Step Solution

1. Step 1: Write the proportion equation
   68,789.75 : 91,728.25 = 91,728.25 : x
2. Step 2: Convert to fraction form
   68,789.75/91,728.25 = 91,728.25/x
3. Step 3: Cross multiply
   68,789.75x = 91,728.25 × 91,728.25
4. Step 4: Simplify right side
   68,789.75x = 8,414,071,848.06
5. Step 5: Solve for x
   x = 8,414,071,848.06/68,789.75
6. Step 6: Final answer
   x = 122,315.78