Finding the Third Proportional to 642.30 and 1,404.42

Step by Step Solution

1. Step 1: Write the proportion equation
   642.30 : 1,404.42 = 1,404.42 : x
2. Step 2: Convert to fraction form
   642.30/1,404.42 = 1,404.42/x
3. Step 3: Cross multiply
   642.30x = 1,404.42 × 1,404.42
4. Step 4: Simplify right side
   642.30x = 1,972,400.80
5. Step 5: Solve for x
   x = 1,972,400.80/642.30
6. Step 6: Final answer
   x = 3,070.82