Finding the Third Proportional to 643.31 and 1,035.56

Step by Step Solution

1. Step 1: Write the proportion equation
   643.31 : 1,035.56 = 1,035.56 : x
2. Step 2: Convert to fraction form
   643.31/1,035.56 = 1,035.56/x
3. Step 3: Cross multiply
   643.31x = 1,035.56 × 1,035.56
4. Step 4: Simplify right side
   643.31x = 1,072,389.69
5. Step 5: Solve for x
   x = 1,072,389.69/643.31
6. Step 6: Final answer
   x = 1,666.98