Finding the Third Proportional to 428,978 and 847,174

Step by Step Solution

1. Step 1: Write the proportion equation
   428,978 : 847,174 = 847,174 : x
2. Step 2: Convert to fraction form
   428,978/847,174 = 847,174/x
3. Step 3: Cross multiply
   428,978x = 847,174 × 847,174
4. Step 4: Simplify right side
   428,978x = 717,703,786,276
5. Step 5: Solve for x
   x = 717,703,786,276/428,978
6. Step 6: Final answer
   x = 1,673,055.00