Finding the Third Proportional to 299,857.50 and 644,178

Step by Step Solution

1. Step 1: Write the proportion equation
   299,857.50 : 644,178 = 644,178 : x
2. Step 2: Convert to fraction form
   299,857.50/644,178 = 644,178/x
3. Step 3: Cross multiply
   299,857.50x = 644,178 × 644,178
4. Step 4: Simplify right side
   299,857.50x = 414,965,295,684
5. Step 5: Solve for x
   x = 414,965,295,684/299,857.50
6. Step 6: Final answer
   x = 1,383,874.99