+0  
 
0
59
2
avatar

At my office, 17 people own cats, 9 people own dogs, and 3 people own both cats and dogs. How many people own a cat or a dog?

 Jun 14, 2020
 #1
avatar+902 
+2

Draw a venn diagram

 

 

(this is more of a boxed diagram as I am unable to upload images with my current browser)

 

cats                                             dogs

|-----------------------|----------------------------|

|                    |             |                            |

|                    |             |                           |

|  14                  |     3       |             6              |

|                    |             |                           |

|-----------------------|----------------------------|

 

Thus there are 14 + 3 + 6 = 23 people who have a cat OR dog.

 Jun 14, 2020
 #2
avatar+1093 
+1

solution(1)

so we have 17-3+9-3=14+6=20 so 30 people own a cat or a dog

 

 

solution(2)

there is 17+9-3=23 people we then do 23-3=20 people who own a cat or a dog

 Jun 14, 2020

11 Online Users