Finding the Third Proportional to 216 and 380.50

Step by Step Solution

1. Step 1: Write the proportion equation
   216 : 380.50 = 380.50 : x
2. Step 2: Convert to fraction form
   216/380.50 = 380.50/x
3. Step 3: Cross multiply
   216x = 380.50 × 380.50
4. Step 4: Simplify right side
   216x = 144,780.25
5. Step 5: Solve for x
   x = 144,780.25/216
6. Step 6: Final answer
   x = 670.28