Question 1134500
z=(x-mean)/sd
>2775 is z>(2775-1875)/640 or z> 900/640 or 1.41. This is probability of 0.0793 or 0.08

>3175 is z>1300/640 or 2.03.  Probability of z between 1.41 and 2.03 is 0.0581 or 0.06

<1075 is z<(-800/640) or < -1.25 and a probability of 0.1056 or 0.11