Finding the Third Proportional to 436,830 and 685,378.50

Step by Step Solution

1. Step 1: Write the proportion equation
   436,830 : 685,378.50 = 685,378.50 : x
2. Step 2: Convert to fraction form
   436,830/685,378.50 = 685,378.50/x
3. Step 3: Cross multiply
   436,830x = 685,378.50 × 685,378.50
4. Step 4: Simplify right side
   436,830x = 469,743,688,262.25
5. Step 5: Solve for x
   x = 469,743,688,262.25/436,830
6. Step 6: Final answer
   x = 1,075,346.68