Finding the Third Proportional to 401.20 and 854.30

Step by Step Solution

1. Step 1: Write the proportion equation
   401.20 : 854.30 = 854.30 : x
2. Step 2: Convert to fraction form
   401.20/854.30 = 854.30/x
3. Step 3: Cross multiply
   401.20x = 854.30 × 854.30
4. Step 4: Simplify right side
   401.20x = 729,823.15
5. Step 5: Solve for x
   x = 729,823.15/401.20
6. Step 6: Final answer
   x = 1,819.09