Finding the Third Proportional to 820.50 and 1,815

Step by Step Solution

1. Step 1: Write the proportion equation
   820.50 : 1,815 = 1,815 : x
2. Step 2: Convert to fraction form
   820.50/1,815 = 1,815/x
3. Step 3: Cross multiply
   820.50x = 1,815 × 1,815
4. Step 4: Simplify right side
   820.50x = 3,294,225
5. Step 5: Solve for x
   x = 3,294,225/820.50
6. Step 6: Final answer
   x = 4,014.90