Finding the Third Proportional to 436.78 and 659.81

Step by Step Solution

1. Step 1: Write the proportion equation
   436.78 : 659.81 = 659.81 : x
2. Step 2: Convert to fraction form
   436.78/659.81 = 659.81/x
3. Step 3: Cross multiply
   436.78x = 659.81 × 659.81
4. Step 4: Simplify right side
   436.78x = 435,352.54
5. Step 5: Solve for x
   x = 435,352.54/436.78
6. Step 6: Final answer
   x = 996.73