Finding the Third Proportional to 42.75 and 72.19

Step by Step Solution

1. Step 1: Write the proportion equation
   42.75 : 72.19 = 72.19 : x
2. Step 2: Convert to fraction form
   42.75/72.19 = 72.19/x
3. Step 3: Cross multiply
   42.75x = 72.19 × 72.19
4. Step 4: Simplify right side
   42.75x = 5,211.04
5. Step 5: Solve for x
   x = 5,211.04/42.75
6. Step 6: Final answer
   x = 121.90