Multiply by 4 by doubling twice. Don't forget the marked answer sheet after ten questions can be printed out.
Multiply by 50 by multiplying by 100 and halving the answer.
Multiply by 16 by multiplying by 8 and doubling the answer.
Just 40 seconds to correctly answer as many as possible. Quite easy so you should get a good score.
Swallow up all the multiples of 6. to get a really high score.