Finding the Third Proportional to 390,882 and 856,578

Step by Step Solution

1. Step 1: Write the proportion equation
   390,882 : 856,578 = 856,578 : x
2. Step 2: Convert to fraction form
   390,882/856,578 = 856,578/x
3. Step 3: Cross multiply
   390,882x = 856,578 × 856,578
4. Step 4: Simplify right side
   390,882x = 733,725,870,084
5. Step 5: Solve for x
   x = 733,725,870,084/390,882
6. Step 6: Final answer
   x = 1,877,103.24