Finding the Third Proportional to 145,978 and 315,944

Step by Step Solution

1. Step 1: Write the proportion equation
   145,978 : 315,944 = 315,944 : x
2. Step 2: Convert to fraction form
   145,978/315,944 = 315,944/x
3. Step 3: Cross multiply
   145,978x = 315,944 × 315,944
4. Step 4: Simplify right side
   145,978x = 99,820,611,136
5. Step 5: Solve for x
   x = 99,820,611,136/145,978
6. Step 6: Final answer
   x = 683,805.86