Finding the Third Proportional to 261,756 and 402,870

Step by Step Solution

1. Step 1: Write the proportion equation
   261,756 : 402,870 = 402,870 : x
2. Step 2: Convert to fraction form
   261,756/402,870 = 402,870/x
3. Step 3: Cross multiply
   261,756x = 402,870 × 402,870
4. Step 4: Simplify right side
   261,756x = 162,304,236,900
5. Step 5: Solve for x
   x = 162,304,236,900/261,756
6. Step 6: Final answer
   x = 620,059.28