Finding the Third Proportional to 853.88 and 1,105.31

Step by Step Solution

1. Step 1: Write the proportion equation
   853.88 : 1,105.31 = 1,105.31 : x
2. Step 2: Convert to fraction form
   853.88/1,105.31 = 1,105.31/x
3. Step 3: Cross multiply
   853.88x = 1,105.31 × 1,105.31
4. Step 4: Simplify right side
   853.88x = 1,221,715.72
5. Step 5: Solve for x
   x = 1,221,715.72/853.88
6. Step 6: Final answer
   x = 1,430.79