Finding the Third Proportional to 820.50 and 1,064.25

Step by Step Solution

1. Step 1: Write the proportion equation
   820.50 : 1,064.25 = 1,064.25 : x
2. Step 2: Convert to fraction form
   820.50/1,064.25 = 1,064.25/x
3. Step 3: Cross multiply
   820.50x = 1,064.25 × 1,064.25
4. Step 4: Simplify right side
   820.50x = 1,132,628.06
5. Step 5: Solve for x
   x = 1,132,628.06/820.50
6. Step 6: Final answer
   x = 1,380.41