Finding the Third Proportional to 288,879.50 and 644,146

Step by Step Solution

1. Step 1: Write the proportion equation
   288,879.50 : 644,146 = 644,146 : x
2. Step 2: Convert to fraction form
   288,879.50/644,146 = 644,146/x
3. Step 3: Cross multiply
   288,879.50x = 644,146 × 644,146
4. Step 4: Simplify right side
   288,879.50x = 414,924,069,316
5. Step 5: Solve for x
   x = 414,924,069,316/288,879.50
6. Step 6: Final answer
   x = 1,436,322.31