Finding the Third Proportional to 640.69 and 973.69

Step by Step Solution

1. Step 1: Write the proportion equation
   640.69 : 973.69 = 973.69 : x
2. Step 2: Convert to fraction form
   640.69/973.69 = 973.69/x
3. Step 3: Cross multiply
   640.69x = 973.69 × 973.69
4. Step 4: Simplify right side
   640.69x = 948,067.35
5. Step 5: Solve for x
   x = 948,067.35/640.69
6. Step 6: Final answer
   x = 1,479.77