Finding the Third Proportional to 300,009 and 438,168

Step by Step Solution

1. Step 1: Write the proportion equation
   300,009 : 438,168 = 438,168 : x
2. Step 2: Convert to fraction form
   300,009/438,168 = 438,168/x
3. Step 3: Cross multiply
   300,009x = 438,168 × 438,168
4. Step 4: Simplify right side
   300,009x = 191,991,196,224
5. Step 5: Solve for x
   x = 191,991,196,224/300,009
6. Step 6: Final answer
   x = 639,951.46