Finding the Third Proportional to 686.81 and 935.72

Step by Step Solution

1. Step 1: Write the proportion equation
   686.81 : 935.72 = 935.72 : x
2. Step 2: Convert to fraction form
   686.81/935.72 = 935.72/x
3. Step 3: Cross multiply
   686.81x = 935.72 × 935.72
4. Step 4: Simplify right side
   686.81x = 875,569.58
5. Step 5: Solve for x
   x = 875,569.58/686.81
6. Step 6: Final answer
   x = 1,274.83