Answer:
0.04865 or 4.9%
Explanation:
This is a binomial distribution function which is expressed as:

Where:
- p=probability of success
- x=number of successful events
- n=size of the sample
Given that p=0.03, n=12 and x=2+, the probability of a cash back is calculated as:
![P(X=x){n\choose x}p^x(1-p)^(n-x)\\\\P(X\geq 2)=1-P(X\leq 1)\\\\=1-[{12\choose 0}0.03^0(0.97)^(12)+{12\choose 1}0.03^1(0.97)^(11)]\\\\\\=1-[0.69384+0.25751]\\\\\\=0.04865](https://img.qammunity.org/2021/formulas/mathematics/middle-school/m20zk2p760nyqrhkbuz4kw4fv89o28dcdf.png)
Hence, the probability of a cash return is 0.04865 or 4.9%