numbergrid [prime numbers]

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PRIME numbers are natural numbers that are divisible by only 1 AND the number itself. An example of a PRIME number is 13. That is because it can only be divided by 1 and 13 without a remainder. Simply click on all of the numbers in the grid which are NOT PRIME NUMBERS. They will disappear and you will be left with a set of numbers which are PRIME NUMBERS. Count them and put the answer into the quiz below the activity. To restart the activity just refresh the page.

PRIME numbers are natural numbers that are divisible by only 1 and the number itself. An example of a PRIME number is 13. That is because it can only be divided by 1 and 13 without a remainder. Simply click on all of the numbers in the grid which are NOT PRIME NUMBERS. They will disappear and you will be left with a set of numbers which are PRIME NUMBERS. Count them and put the answer into the quiz below the activity. To restart the activity just refresh the page.

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