Finding the Third Proportional to 149,901 and 321,123

Step by Step Solution

1. Step 1: Write the proportion equation
   149,901 : 321,123 = 321,123 : x
2. Step 2: Convert to fraction form
   149,901/321,123 = 321,123/x
3. Step 3: Cross multiply
   149,901x = 321,123 × 321,123
4. Step 4: Simplify right side
   149,901x = 103,119,981,129
5. Step 5: Solve for x
   x = 103,119,981,129/149,901
6. Step 6: Final answer
   x = 687,920.57