Finding the Third Proportional to 200.72 and 411.28

Step by Step Solution

1. Step 1: Write the proportion equation
   200.72 : 411.28 = 411.28 : x
2. Step 2: Convert to fraction form
   200.72/411.28 = 411.28/x
3. Step 3: Cross multiply
   200.72x = 411.28 × 411.28
4. Step 4: Simplify right side
   200.72x = 169,152.27
5. Step 5: Solve for x
   x = 169,152.27/200.72
6. Step 6: Final answer
   x = 842.73