Finding the Third Proportional to 643.50 and 982.69

Step by Step Solution

1. Step 1: Write the proportion equation
   643.50 : 982.69 = 982.69 : x
2. Step 2: Convert to fraction form
   643.50/982.69 = 982.69/x
3. Step 3: Cross multiply
   643.50x = 982.69 × 982.69
4. Step 4: Simplify right side
   643.50x = 965,674.72
5. Step 5: Solve for x
   x = 965,674.72/643.50
6. Step 6: Final answer
   x = 1,500.66