Finding the Third Proportional to 1,087.31 and 1,246.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,087.31 : 1,246.78 = 1,246.78 : x
2. Step 2: Convert to fraction form
   1,087.31/1,246.78 = 1,246.78/x
3. Step 3: Cross multiply
   1,087.31x = 1,246.78 × 1,246.78
4. Step 4: Simplify right side
   1,087.31x = 1,554,463.49
5. Step 5: Solve for x
   x = 1,554,463.49/1,087.31
6. Step 6: Final answer
   x = 1,429.64