janani11 wrote:
as 10% of birds=80, therefore, the total animals in the zoo ( 100%)=800.
Let's add X more birds to make the percentage of Birds AT LEAST 20 % of the total.
So, (80+x) is equal to or greater than 20% of ( 800+X)
80+x = 0.2(800+x)
80+x = 160+0.2x
-80= -0.8x
X=100
By calculation we get, X is greater than or equal to 100.
That is, if at least 100 birds are added, then we can get the desired percentage of bird population in the zoo.
What would be the problem if we consider, There are a total of 100 birds. Thanks.
10+x = 0.2(100+x)
10+x = 20+0.2x
10= 0.8x
X=12.5