At what temperature on the Fahrenheit scale will the reading be double of the reading on the Celsius scale?

At what temperature on the Fahrenheit scale will the reading be double

1.	At what temperature on the Fahrenheit scale will the reading be double of the reading on the Celsius scale?
Answer» `340^(@)` F `240.6^(@)` F `330^(@)` F `320^(@)` F ANSWER :D