Finding the Third Proportional to 287.06 and 610.69

Step by Step Solution

1. Step 1: Write the proportion equation
   287.06 : 610.69 = 610.69 : x
2. Step 2: Convert to fraction form
   287.06/610.69 = 610.69/x
3. Step 3: Cross multiply
   287.06x = 610.69 × 610.69
4. Step 4: Simplify right side
   287.06x = 372,939.22
5. Step 5: Solve for x
   x = 372,939.22/287.06
6. Step 6: Final answer
   x = 1,299.16