Finding the Third Proportional to 681.50 and 900.50

Step by Step Solution

1. Step 1: Write the proportion equation
   681.50 : 900.50 = 900.50 : x
2. Step 2: Convert to fraction form
   681.50/900.50 = 900.50/x
3. Step 3: Cross multiply
   681.50x = 900.50 × 900.50
4. Step 4: Simplify right side
   681.50x = 810,900.25
5. Step 5: Solve for x
   x = 810,900.25/681.50
6. Step 6: Final answer
   x = 1,189.88