Finding the Third Proportional to 139,378.50 and 303,621

Step by Step Solution

1. Step 1: Write the proportion equation
   139,378.50 : 303,621 = 303,621 : x
2. Step 2: Convert to fraction form
   139,378.50/303,621 = 303,621/x
3. Step 3: Cross multiply
   139,378.50x = 303,621 × 303,621
4. Step 4: Simplify right side
   139,378.50x = 92,185,711,641
5. Step 5: Solve for x
   x = 92,185,711,641/139,378.50
6. Step 6: Final answer
   x = 661,405.54