Finding the Third Proportional to 200,261 and 309,978

Step by Step Solution

1. Step 1: Write the proportion equation
   200,261 : 309,978 = 309,978 : x
2. Step 2: Convert to fraction form
   200,261/309,978 = 309,978/x
3. Step 3: Cross multiply
   200,261x = 309,978 × 309,978
4. Step 4: Simplify right side
   200,261x = 96,086,360,484
5. Step 5: Solve for x
   x = 96,086,360,484/200,261
6. Step 6: Final answer
   x = 479,805.66