Finding the Third Proportional to 39.75 and 71.25

Step by Step Solution

1. Step 1: Write the proportion equation
   39.75 : 71.25 = 71.25 : x
2. Step 2: Convert to fraction form
   39.75/71.25 = 71.25/x
3. Step 3: Cross multiply
   39.75x = 71.25 × 71.25
4. Step 4: Simplify right side
   39.75x = 5,076.56
5. Step 5: Solve for x
   x = 5,076.56/39.75
6. Step 6: Final answer
   x = 127.71