Finding the Third Proportional to 307.69 and 571.78

Step by Step Solution

1. Step 1: Write the proportion equation
   307.69 : 571.78 = 571.78 : x
2. Step 2: Convert to fraction form
   307.69/571.78 = 571.78/x
3. Step 3: Cross multiply
   307.69x = 571.78 × 571.78
4. Step 4: Simplify right side
   307.69x = 326,933.80
5. Step 5: Solve for x
   x = 326,933.80/307.69
6. Step 6: Final answer
   x = 1,062.55