Finding the Third Proportional to 681.38 and 899.81

Step by Step Solution

1. Step 1: Write the proportion equation
   681.38 : 899.81 = 899.81 : x
2. Step 2: Convert to fraction form
   681.38/899.81 = 899.81/x
3. Step 3: Cross multiply
   681.38x = 899.81 × 899.81
4. Step 4: Simplify right side
   681.38x = 809,662.54
5. Step 5: Solve for x
   x = 809,662.54/681.38
6. Step 6: Final answer
   x = 1,188.28