Finding the Third Proportional to 356,715.50 and 489,146

Step by Step Solution

1. Step 1: Write the proportion equation
   356,715.50 : 489,146 = 489,146 : x
2. Step 2: Convert to fraction form
   356,715.50/489,146 = 489,146/x
3. Step 3: Cross multiply
   356,715.50x = 489,146 × 489,146
4. Step 4: Simplify right side
   356,715.50x = 239,263,809,316
5. Step 5: Solve for x
   x = 239,263,809,316/356,715.50
6. Step 6: Final answer
   x = 670,741.28