Finding the Third Proportional to 202,920 and 315,430.50

Step by Step Solution

1. Step 1: Write the proportion equation
   202,920 : 315,430.50 = 315,430.50 : x
2. Step 2: Convert to fraction form
   202,920/315,430.50 = 315,430.50/x
3. Step 3: Cross multiply
   202,920x = 315,430.50 × 315,430.50
4. Step 4: Simplify right side
   202,920x = 99,496,400,330.25
5. Step 5: Solve for x
   x = 99,496,400,330.25/202,920
6. Step 6: Final answer
   x = 490,323.28