Finding the Third Proportional to 68.50 and 90.50

Step by Step Solution

1. Step 1: Write the proportion equation
   68.50 : 90.50 = 90.50 : x
2. Step 2: Convert to fraction form
   68.50/90.50 = 90.50/x
3. Step 3: Cross multiply
   68.50x = 90.50 × 90.50
4. Step 4: Simplify right side
   68.50x = 8,190.25
5. Step 5: Solve for x
   x = 8,190.25/68.50
6. Step 6: Final answer
   x = 119.57