Finding the Third Proportional to 100,917 and 212,290.50

Step by Step Solution

1. Step 1: Write the proportion equation
   100,917 : 212,290.50 = 212,290.50 : x
2. Step 2: Convert to fraction form
   100,917/212,290.50 = 212,290.50/x
3. Step 3: Cross multiply
   100,917x = 212,290.50 × 212,290.50
4. Step 4: Simplify right side
   100,917x = 45,067,256,390.25
5. Step 5: Solve for x
   x = 45,067,256,390.25/100,917
6. Step 6: Final answer
   x = 446,577.45