Work out the missing number to make the total 100. Printable answer page available after 10 questions.
Revise pairs of numbers that total one. Remember to put a zero in the units for these questions.
Find the missing number to make the total of 1000. All multiples of 50. printable answer page after 10 questions.
More practice at doubling multiples of 10. printable answer page after 10 questions.
Double multiples of 100 mentally.
Just one minute to double as many numbers up to 100 as possible. Some are much easier than others! 20 plus is a good score.
Hit the space stations to get a question. Correct answers gain points. Avoid hitting the rockets or giving a wrong answer! It gets really hard as your score approaches 100!