Finding the Third Proportional to 261,780 and 420,004.50

Step by Step Solution

1. Step 1: Write the proportion equation
   261,780 : 420,004.50 = 420,004.50 : x
2. Step 2: Convert to fraction form
   261,780/420,004.50 = 420,004.50/x
3. Step 3: Cross multiply
   261,780x = 420,004.50 × 420,004.50
4. Step 4: Simplify right side
   261,780x = 176,403,780,020.25
5. Step 5: Solve for x
   x = 176,403,780,020.25/261,780
6. Step 6: Final answer
   x = 673,862.71