A numbered card is randomly selected from a set of similar cards numbered from 1 to 30 with no repetition. Find the probability of getting a card holding a number that is NOT divisible by 10.
The probability of an event is the ratio between the number of
outcomes of the event and the number of all possible outcomes in
the sample space.
To find the probability that a randomly selected card holds a
number that is NOT divisible by 10, divide the number of cards
that are NOT divisible by 10 by the total number of cards.
There are 3 cards that hold numbers that are divisible by 10 (10,
20, and 30), so there are cards that hold numbers that
are NOT divisible by 10.