pp-t2-ds46

[ggyygpi]

3000families live in a certain town. how many families who live in the town own neither a car nor a tv set?
1).of the families who live in the town, 2980 own a car
2).of the families who live in the town, 2970 own both a car and a tv set
答案E
不是B麼? 還是我看錯題目呢??

[Huang Hsin-Yi]

遇到這種有x或y的題目,就給它自動列個表
所有的人,可分為

car, tv------------1
no car, tv--------2
car, no tv--------3
no car, no tv----4

1+2++3+4=3000 問4=?
(1) 1+3=2980-----insufficient
(2) 1 =2970-----insufficient
(1)(2)還是解不出4

therefore E

[ggyygpi]

謝謝你 感恩謝謝你唷