Finding the Third Proportional to 842.50 and 1,800

Step by Step Solution

1. Step 1: Write the proportion equation
   842.50 : 1,800 = 1,800 : x
2. Step 2: Convert to fraction form
   842.50/1,800 = 1,800/x
3. Step 3: Cross multiply
   842.50x = 1,800 × 1,800
4. Step 4: Simplify right side
   842.50x = 3,240,000
5. Step 5: Solve for x
   x = 3,240,000/842.50
6. Step 6: Final answer
   x = 3,845.70