Finding the Third Proportional to 451.31 and 715.78

Step by Step Solution

1. Step 1: Write the proportion equation
   451.31 : 715.78 = 715.78 : x
2. Step 2: Convert to fraction form
   451.31/715.78 = 715.78/x
3. Step 3: Cross multiply
   451.31x = 715.78 × 715.78
4. Step 4: Simplify right side
   451.31x = 512,342.80
5. Step 5: Solve for x
   x = 512,342.80/451.31
6. Step 6: Final answer
   x = 1,135.23