Finding the Third Proportional to 86,245.50 and 128,836.50

Step by Step Solution

1. Step 1: Write the proportion equation
   86,245.50 : 128,836.50 = 128,836.50 : x
2. Step 2: Convert to fraction form
   86,245.50/128,836.50 = 128,836.50/x
3. Step 3: Cross multiply
   86,245.50x = 128,836.50 × 128,836.50
4. Step 4: Simplify right side
   86,245.50x = 16,598,843,732.25
5. Step 5: Solve for x
   x = 16,598,843,732.25/86,245.50
6. Step 6: Final answer
   x = 192,460.40