In a surey of 375 dog and cat owners there were 215 dog owners and 193 cat owners. how many in the survey own a dog
2 answers:
First, draw venn diagram and determine how many people own both cat and dog. See image attached.
x represents the number of people own both cat and dog
dog only owner + cat only owner + both cat and dog owner = 375
215 - x + 193 - x + x = 375
408 - x = 375
x = 408 - 375
x = 33
The number of people own both cat and dog is 33
Second, find the number of people own dog only
dog only = 215 - 33
dog only = 182
The number of people own dog only is 182
x represents the number of people own both cat and dog
dog only owner + cat only owner + both cat and dog owner = 375
215 - x + 193 - x + x = 375
408 - x = 375
x = 408 - 375
x = 33
The number of people own both cat and dog is 33
Second, find the number of people own dog only
dog only = 215 - 33
dog only = 182
The number of people own dog only is 182
You might be interested in
Let x gallons be the amount of pure antifreeze that should be added to the 30% solution to produce a solution that is 65% antifreeze. Then the total amount of antifreeze solution will be x+3 gallons.
There are 30% of pure antifreeze in 3 gallons of solution, then
3 gallons - 100%,
a gallons - 30%,
where a gallons is the amount of pure antifreeze in given solution.
Mathematically,
Now in new solution there will be x+0.9 gallons of pure antefreeze.
x+3 gallons - 100%,
x+0.9 - 65%
or
Answer: he should add 3 gallons of pure antifreeze.