Finding the Third Proportional to 287,367 and 422,698.50

Step by Step Solution

1. Step 1: Write the proportion equation
   287,367 : 422,698.50 = 422,698.50 : x
2. Step 2: Convert to fraction form
   287,367/422,698.50 = 422,698.50/x
3. Step 3: Cross multiply
   287,367x = 422,698.50 × 422,698.50
4. Step 4: Simplify right side
   287,367x = 178,674,021,902.25
5. Step 5: Solve for x
   x = 178,674,021,902.25/287,367
6. Step 6: Final answer
   x = 621,762.49