Finding the Third Proportional to 287.06 and 636.56

Step by Step Solution

1. Step 1: Write the proportion equation
   287.06 : 636.56 = 636.56 : x
2. Step 2: Convert to fraction form
   287.06/636.56 = 636.56/x
3. Step 3: Cross multiply
   287.06x = 636.56 × 636.56
4. Step 4: Simplify right side
   287.06x = 405,211.82
5. Step 5: Solve for x
   x = 405,211.82/287.06
6. Step 6: Final answer
   x = 1,411.58