Finding the Third Proportional to 261,370 and 391,010

Step by Step Solution

1. Step 1: Write the proportion equation
   261,370 : 391,010 = 391,010 : x
2. Step 2: Convert to fraction form
   261,370/391,010 = 391,010/x
3. Step 3: Cross multiply
   261,370x = 391,010 × 391,010
4. Step 4: Simplify right side
   261,370x = 152,888,820,100
5. Step 5: Solve for x
   x = 152,888,820,100/261,370
6. Step 6: Final answer
   x = 584,951.68