Finding the Third Proportional to 388,760 and 580,142

Step by Step Solution

1. Step 1: Write the proportion equation
   388,760 : 580,142 = 580,142 : x
2. Step 2: Convert to fraction form
   388,760/580,142 = 580,142/x
3. Step 3: Cross multiply
   388,760x = 580,142 × 580,142
4. Step 4: Simplify right side
   388,760x = 336,564,740,164
5. Step 5: Solve for x
   x = 336,564,740,164/388,760
6. Step 6: Final answer
   x = 865,739.12