Finding the Third Proportional to 172.55 and 265.15

Step by Step Solution

1. Step 1: Write the proportion equation
   172.55 : 265.15 = 265.15 : x
2. Step 2: Convert to fraction form
   172.55/265.15 = 265.15/x
3. Step 3: Cross multiply
   172.55x = 265.15 × 265.15
4. Step 4: Simplify right side
   172.55x = 70,303.69
5. Step 5: Solve for x
   x = 70,303.69/172.55
6. Step 6: Final answer
   x = 407.45