Finding the Third Proportional to 411.13 and 611.89

Step by Step Solution

1. Step 1: Write the proportion equation
   411.13 : 611.89 = 611.89 : x
2. Step 2: Convert to fraction form
   411.13/611.89 = 611.89/x
3. Step 3: Cross multiply
   411.13x = 611.89 × 611.89
4. Step 4: Simplify right side
   411.13x = 374,409.54
5. Step 5: Solve for x
   x = 374,409.54/411.13
6. Step 6: Final answer
   x = 910.68