Cards numbered 1 through 30 are placed in a bag and shuffled. One card is chosen at random. What is the probability of randomly selecting a number less than or equal to 5, or a multiple of 7?

Guest Aug 27, 2018

#1**+2 **

Less than or equal to 5....there are 5 cards ...1,2,3,4,5

Multiple of 7....there are 4 cards .... 7, 14, 21 , 28

So.... [5 + 4 ] / 30 = 9 / 30 = 3 /10

CPhill
Aug 27, 2018

#2**+2 **

In order to find the probability of a certain event, we need to set up the fraction; \(\frac{p(successful)}{p(possible)}\). Let's see how many numbers are successful:

Less than or equal to 5: \(1, 2, 3, 4, 5\)

Multiple of 7: \(7, 14, 21, 28\).

These nine numbers are successful, so your probability would be \(\frac{9}{30} = \frac{3}{10}\).

- Daisy

dierdurst
Aug 27, 2018