Finding the Third Proportional to 100,577.50 and 209,422.50

Step by Step Solution

1. Step 1: Write the proportion equation
   100,577.50 : 209,422.50 = 209,422.50 : x
2. Step 2: Convert to fraction form
   100,577.50/209,422.50 = 209,422.50/x
3. Step 3: Cross multiply
   100,577.50x = 209,422.50 × 209,422.50
4. Step 4: Simplify right side
   100,577.50x = 43,857,783,506.25
5. Step 5: Solve for x
   x = 43,857,783,506.25/100,577.50
6. Step 6: Final answer
   x = 436,059.59