In a group of 1000 people, 750 persons are environment friendly and 400 people are concerned about saving natural resources - Maths - Sets

Question

In a group of 1000 people, 750 persons are environment friendly
and 400 people are concerned about saving natural resources How
many are environment friendly only? How many are concerned about
saving natural resources only? How many are concerned about both?
Do u have the same concern?

Anuradha Sharma · Accepted Answer

The Venn diagram can be given as,
<img alt="" src=
"https://s3mn%20mnimgs%20com/img/shared/content_ck_images/images/2313(1)%20png"
style="width: 243px; height: 222px;">
Now representing environment friendly as EV and natural resource
concerned people as 400 and assuming there is no person out of
these two mentioned category ,
So
nEF=750 and nNR=400 and nEF∪NR=1000So using property,  nEF∪NR=nEF+ nNR-nEF∩NR1000=750+400-nEF∩NRor nEF∩NR =150Now only Environment friendly =nEF- nEF∩NR =750-150=600and only natural resource concerned people= nNR-nEF∩NR=400-150=250

In a group of 1000 people, 750 persons are environment friendly and 400 people are concerned about saving natural resources. How many are environment friendly only? How many are concerned about saving natural resources only? How many are concerned about both? Do u have the same concern?