Finding the Third Proportional to 99,909 and 209,054

Step by Step Solution

1. Step 1: Write the proportion equation
   99,909 : 209,054 = 209,054 : x
2. Step 2: Convert to fraction form
   99,909/209,054 = 209,054/x
3. Step 3: Cross multiply
   99,909x = 209,054 × 209,054
4. Step 4: Simplify right side
   99,909x = 43,703,574,916
5. Step 5: Solve for x
   x = 43,703,574,916/99,909
6. Step 6: Final answer
   x = 437,433.81