Finding the Third Proportional to 69.50 and 99.50

Step by Step Solution

1. Step 1: Write the proportion equation
   69.50 : 99.50 = 99.50 : x
2. Step 2: Convert to fraction form
   69.50/99.50 = 99.50/x
3. Step 3: Cross multiply
   69.50x = 99.50 × 99.50
4. Step 4: Simplify right side
   69.50x = 9,900.25
5. Step 5: Solve for x
   x = 9,900.25/69.50
6. Step 6: Final answer
   x = 142.45