SOLUTION: A survey of 830 workers in a plant indicated that 520 owned houses, 560 owned cars, 275 owned boats, 350 owned cars and houses, 220 owned houses and boats, 160 owned cars and boats

Algebra.Com
Question 1145089: A survey of 830 workers in a plant indicated that 520 owned houses, 560 owned cars, 275 owned boats, 350 owned cars and houses, 220 owned houses and boats, 160 owned cars and boats, and 150 owned all three.
How many of the workers did not own any of the three items?
How many of the workers owned only two of the items?

Answer by ikleyn(52776)   (Show Source): You can put this solution on YOUR website!
.
(a)  First calculate the number of those workers who own at least one of the items.


     For it, calculate the alternate sum


         560 + 560 + 275 - 350 - 220 - 160 + 150 = 815.


     The rest 830 - 815 = 15 workers do not own any of the three items.    ANSWER



(b)  Only cars and houses   350 - 150 = 200.

     Only cars and boats    160 - 150 =  10.

     Only houses and boats  220 - 150 =  70.


     The subsets of workers counted in the previous 3 lines are DISJOINT.


     Therefore, the number of workers who own only two items is  220 + 10 + 70 = 300.    ANSWER

------------------

For more details and explanations, read the lessons
    - Advanced problems on counting elements in sub-sets of a given finite set
    - Challenging problems on counting elements in subsets of a given finite set
in this site, where you will find many similar solved problems.


RELATED QUESTIONS

A survey of 1180 workers in a plant indicated that 620 owned houses, 680 owned cars, 445... (answered by Shin123)
A survey of 1045 workers in a plant indicated that 660 owned houses, 800 owned cars, 355... (answered by ikleyn)
In survey of 900 workers 600 owned houses,500 owned cars and 345 owned boat,300 owned... (answered by math_tutor2020,ikleyn)
A survey of 51 pet owners revealed that 32 owned dogs, 38 owned cats, and 3 owned neither (answered by edjones)
A survey of 51 pet owners revealed that 32 owned dogs, 38 owned cats, and 3 owned neither (answered by sudhanshu_kmr)
A survey of 51 pet owners revealed that 32 owned dogs, 38 owned cats, and 3 owned neither (answered by sudhanshu_kmr)
From a survey of 600 college students, a marketing research company found that 400... (answered by checkley77)
A survey of 53 pet owners revealed that 25 own chickens, 21 owned pigs, 23 owned goats,... (answered by stanbon)
A survey of 51 pet owners revealed that 24 owned dogs, 28 owned cats, 11 owned turtles,... (answered by rfer)