Finding the Third Proportional to 386,440 and 830,020

Step by Step Solution

1. Step 1: Write the proportion equation
   386,440 : 830,020 = 830,020 : x
2. Step 2: Convert to fraction form
   386,440/830,020 = 830,020/x
3. Step 3: Cross multiply
   386,440x = 830,020 × 830,020
4. Step 4: Simplify right side
   386,440x = 688,933,200,400
5. Step 5: Solve for x
   x = 688,933,200,400/386,440
6. Step 6: Final answer
   x = 1,782,768.87