Finding the Third Proportional to 389,488 and 851,072

Step by Step Solution

1. Step 1: Write the proportion equation
   389,488 : 851,072 = 851,072 : x
2. Step 2: Convert to fraction form
   389,488/851,072 = 851,072/x
3. Step 3: Cross multiply
   389,488x = 851,072 × 851,072
4. Step 4: Simplify right side
   389,488x = 724,323,549,184
5. Step 5: Solve for x
   x = 724,323,549,184/389,488
6. Step 6: Final answer
   x = 1,859,681.30