Finding the Third Proportional to 551,057 and 851,139

Step by Step Solution

1. Step 1: Write the proportion equation
   551,057 : 851,139 = 851,139 : x
2. Step 2: Convert to fraction form
   551,057/851,139 = 851,139/x
3. Step 3: Cross multiply
   551,057x = 851,139 × 851,139
4. Step 4: Simplify right side
   551,057x = 724,437,597,321
5. Step 5: Solve for x
   x = 724,437,597,321/551,057
6. Step 6: Final answer
   x = 1,314,632.78