Finding the Third Proportional to 987.69 and 1,325.31

Step by Step Solution

1. Step 1: Write the proportion equation
   987.69 : 1,325.31 = 1,325.31 : x
2. Step 2: Convert to fraction form
   987.69/1,325.31 = 1,325.31/x
3. Step 3: Cross multiply
   987.69x = 1,325.31 × 1,325.31
4. Step 4: Simplify right side
   987.69x = 1,756,453.22
5. Step 5: Solve for x
   x = 1,756,453.22/987.69
6. Step 6: Final answer
   x = 1,778.35