Finding the Third Proportional to 402,408 and 870,426

Step by Step Solution

1. Step 1: Write the proportion equation
   402,408 : 870,426 = 870,426 : x
2. Step 2: Convert to fraction form
   402,408/870,426 = 870,426/x
3. Step 3: Cross multiply
   402,408x = 870,426 × 870,426
4. Step 4: Simplify right side
   402,408x = 757,641,421,476
5. Step 5: Solve for x
   x = 757,641,421,476/402,408
6. Step 6: Final answer
   x = 1,882,769.28