Finding the Third Proportional to 510.50 and 686.25

Step by Step Solution

1. Step 1: Write the proportion equation
   510.50 : 686.25 = 686.25 : x
2. Step 2: Convert to fraction form
   510.50/686.25 = 686.25/x
3. Step 3: Cross multiply
   510.50x = 686.25 × 686.25
4. Step 4: Simplify right side
   510.50x = 470,939.06
5. Step 5: Solve for x
   x = 470,939.06/510.50
6. Step 6: Final answer
   x = 922.51