Finding the Third Proportional to 209,968.50 and 318,840

Step by Step Solution

1. Step 1: Write the proportion equation
   209,968.50 : 318,840 = 318,840 : x
2. Step 2: Convert to fraction form
   209,968.50/318,840 = 318,840/x
3. Step 3: Cross multiply
   209,968.50x = 318,840 × 318,840
4. Step 4: Simplify right side
   209,968.50x = 101,658,945,600
5. Step 5: Solve for x
   x = 101,658,945,600/209,968.50
6. Step 6: Final answer
   x = 484,162.84