Finding the Third Proportional to 878 and 1,365.50

Step by Step Solution

1. Step 1: Write the proportion equation
   878 : 1,365.50 = 1,365.50 : x
2. Step 2: Convert to fraction form
   878/1,365.50 = 1,365.50/x
3. Step 3: Cross multiply
   878x = 1,365.50 × 1,365.50
4. Step 4: Simplify right side
   878x = 1,864,590.25
5. Step 5: Solve for x
   x = 1,864,590.25/878
6. Step 6: Final answer
   x = 2,123.68