Finding the Third Proportional to 401.63 and 636.38

Step by Step Solution

1. Step 1: Write the proportion equation
   401.63 : 636.38 = 636.38 : x
2. Step 2: Convert to fraction form
   401.63/636.38 = 636.38/x
3. Step 3: Cross multiply
   401.63x = 636.38 × 636.38
4. Step 4: Simplify right side
   401.63x = 404,973.14
5. Step 5: Solve for x
   x = 404,973.14/401.63
6. Step 6: Final answer
   x = 1,008.34