Finding the Third Proportional to 78,719.50 and 91,515.50

Step by Step Solution

1. Step 1: Write the proportion equation
   78,719.50 : 91,515.50 = 91,515.50 : x
2. Step 2: Convert to fraction form
   78,719.50/91,515.50 = 91,515.50/x
3. Step 3: Cross multiply
   78,719.50x = 91,515.50 × 91,515.50
4. Step 4: Simplify right side
   78,719.50x = 8,375,086,740.25
5. Step 5: Solve for x
   x = 8,375,086,740.25/78,719.50
6. Step 6: Final answer
   x = 106,391.51