Finding the Third Proportional to 31.50 and 69.61

Step by Step Solution

1. Step 1: Write the proportion equation
   31.50 : 69.61 = 69.61 : x
2. Step 2: Convert to fraction form
   31.50/69.61 = 69.61/x
3. Step 3: Cross multiply
   31.50x = 69.61 × 69.61
4. Step 4: Simplify right side
   31.50x = 4,845.47
5. Step 5: Solve for x
   x = 4,845.47/31.50
6. Step 6: Final answer
   x = 153.82