Finding the Third Proportional to 499.50 and 647.25

Step by Step Solution

1. Step 1: Write the proportion equation
   499.50 : 647.25 = 647.25 : x
2. Step 2: Convert to fraction form
   499.50/647.25 = 647.25/x
3. Step 3: Cross multiply
   499.50x = 647.25 × 647.25
4. Step 4: Simplify right side
   499.50x = 418,932.56
5. Step 5: Solve for x
   x = 418,932.56/499.50
6. Step 6: Final answer
   x = 838.70