Answer:
Yes the sample can be use to make inference
Step-by-step explanation:
The inference is possible if the conditions:
p*n > 10 and q*n > 10
where p and q are the proportion probability of success and q = 1 - p
n is sample size
Then p = 12 / 30 = 0,4 q = 1 - 0,4 q = 0,6
And p*n = 0,4 * 30 = 12 12 > 10
And q*n = 0,6 * 30 = 18 18 > 10
Therefore with that sample the conditions to approximate the binomial distribution to a Normal distribution are met