Finding the Third Proportional to 638.72 and 847.69

Step by Step Solution

1. Step 1: Write the proportion equation
   638.72 : 847.69 = 847.69 : x
2. Step 2: Convert to fraction form
   638.72/847.69 = 847.69/x
3. Step 3: Cross multiply
   638.72x = 847.69 × 847.69
4. Step 4: Simplify right side
   638.72x = 718,574.10
5. Step 5: Solve for x
   x = 718,574.10/638.72
6. Step 6: Final answer
   x = 1,125.02