the n term of a sequence is in=(2/3)^ n-1, write down the first three term and show that the sum, sn of the first n term of the series is 3(1-2/3^n)​

There are 10 chicks on ginger's farm .she has 2 chicks in one outdoor pen and 5 chicks in another. the rest of the chicks are in the barn.what is the fraction of total chicks in outdoor pens?