Finding the Third Proportional to 172.69 and 269.53

Step by Step Solution

1. Step 1: Write the proportion equation
   172.69 : 269.53 = 269.53 : x
2. Step 2: Convert to fraction form
   172.69/269.53 = 269.53/x
3. Step 3: Cross multiply
   172.69x = 269.53 × 269.53
4. Step 4: Simplify right side
   172.69x = 72,647.09
5. Step 5: Solve for x
   x = 72,647.09/172.69
6. Step 6: Final answer
   x = 420.69