Finding the Third Proportional to 817.50 and 1,243.50

Step by Step Solution

1. Step 1: Write the proportion equation
   817.50 : 1,243.50 = 1,243.50 : x
2. Step 2: Convert to fraction form
   817.50/1,243.50 = 1,243.50/x
3. Step 3: Cross multiply
   817.50x = 1,243.50 × 1,243.50
4. Step 4: Simplify right side
   817.50x = 1,546,292.25
5. Step 5: Solve for x
   x = 1,546,292.25/817.50
6. Step 6: Final answer
   x = 1,891.49