Finding the Third Proportional to 448,400 and 666,212

Step by Step Solution

1. Step 1: Write the proportion equation
   448,400 : 666,212 = 666,212 : x
2. Step 2: Convert to fraction form
   448,400/666,212 = 666,212/x
3. Step 3: Cross multiply
   448,400x = 666,212 × 666,212
4. Step 4: Simplify right side
   448,400x = 443,838,428,944
5. Step 5: Solve for x
   x = 443,838,428,944/448,400
6. Step 6: Final answer
   x = 989,827.00