Finding the Third Proportional to 216.42 and 311.46

Step by Step Solution

1. Step 1: Write the proportion equation
   216.42 : 311.46 = 311.46 : x
2. Step 2: Convert to fraction form
   216.42/311.46 = 311.46/x
3. Step 3: Cross multiply
   216.42x = 311.46 × 311.46
4. Step 4: Simplify right side
   216.42x = 97,008.83
5. Step 5: Solve for x
   x = 97,008.83/216.42
6. Step 6: Final answer
   x = 448.24