Finding the Third Proportional to 100,399.50 and 209,122

Step by Step Solution

1. Step 1: Write the proportion equation
   100,399.50 : 209,122 = 209,122 : x
2. Step 2: Convert to fraction form
   100,399.50/209,122 = 209,122/x
3. Step 3: Cross multiply
   100,399.50x = 209,122 × 209,122
4. Step 4: Simplify right side
   100,399.50x = 43,732,010,884
5. Step 5: Solve for x
   x = 43,732,010,884/100,399.50
6. Step 6: Final answer
   x = 435,579.97