The given information we have:
The average or mean:
![\mu=75](https://img.qammunity.org/2023/formulas/mathematics/college/njup8226ta8nzbxd8ghwxvzflq6nakhxr7.png)
The standard deviation:
![\sigma=8](https://img.qammunity.org/2023/formulas/mathematics/college/7hulmrbht0w3n843nxm75a52k14acl9x5x.png)
Since Andrew scored 1.25 standard deviations below the mean, the expression to calculate its exam score will be:
![\mu-1.25\sigma](https://img.qammunity.org/2023/formulas/mathematics/college/vsm746cfawvwydh5t168tqptn43x0t4new.png)
Substituting the mean and the standard deviation:
![75-1.25(8)](https://img.qammunity.org/2023/formulas/mathematics/college/nnrclwirz8pvvy5fxqr5gjpl3ozcyg5dhi.png)
And solving the operations:
![75-10](https://img.qammunity.org/2023/formulas/mathematics/college/d54d7dve7jz8urhgfhkj7487eerkewr7di.png)
which gives us the following result:
![65](https://img.qammunity.org/2023/formulas/mathematics/college/eba6ghbfr64hv7qemllzsxj0a75tvqj9zp.png)
Answer: Andrew's exam score is 65