Finding the Third Proportional to 139,619 and 208,864

Step by Step Solution

1. Step 1: Write the proportion equation
   139,619 : 208,864 = 208,864 : x
2. Step 2: Convert to fraction form
   139,619/208,864 = 208,864/x
3. Step 3: Cross multiply
   139,619x = 208,864 × 208,864
4. Step 4: Simplify right side
   139,619x = 43,624,170,496
5. Step 5: Solve for x
   x = 43,624,170,496/139,619
6. Step 6: Final answer
   x = 312,451.53