Finding the Third Proportional to 80,578 and 172,820

Step by Step Solution

1. Step 1: Write the proportion equation
   80,578 : 172,820 = 172,820 : x
2. Step 2: Convert to fraction form
   80,578/172,820 = 172,820/x
3. Step 3: Cross multiply
   80,578x = 172,820 × 172,820
4. Step 4: Simplify right side
   80,578x = 29,866,752,400
5. Step 5: Solve for x
   x = 29,866,752,400/80,578
6. Step 6: Final answer
   x = 370,656.41