Finding the Third Proportional to 300,008 and 438,166

Step by Step Solution

1. Step 1: Write the proportion equation
   300,008 : 438,166 = 438,166 : x
2. Step 2: Convert to fraction form
   300,008/438,166 = 438,166/x
3. Step 3: Cross multiply
   300,008x = 438,166 × 438,166
4. Step 4: Simplify right side
   300,008x = 191,989,443,556
5. Step 5: Solve for x
   x = 191,989,443,556/300,008
6. Step 6: Final answer
   x = 639,947.75