The number of antelope in a certain herd increases every year at a constant rate. If there are 500 antelope in the herd today, how many years will it take for the number of antelope to double?

today count of antelope = 500
let the antelope increase by k percent every year

(1) Ten years from now, there will be more than ten times the current number of antelope in the herd.

after ten years increased wil be 500(1+k/100)^10
now 500(1+k/100)^10> 500*10
(1+k/100)^10>10
k>somevalue

We donot know what is the exact value of K, so we cannot comment on when the count doubles.

INSUFF

(2) If the herd were to grow in number at twice its current rate, there would be 980 antelope in the group in two years

now the new rate is 2k
500(1+2k/100)^2 = 980
We will get some value for k.

Hence we can calculate when the count can double.

pick B

what is OA?

stmnt 1 is insuff : as we have > some value. A small variation in stmnt 1 such as after 10 years,it will =500*10 then stmnt 1 would have been suff.

Stmnt 2: suff ,as we get a value