What is the probability of getting either blue or green on a spinner that is 3/10 green and 1/5 blue

Scores on a university exam are normally distributed with a mean of 78 and a standard deviation of 8. the professor teaching the class declares that a score of 70 or higher is required for a grade of at least “c.” using the 68-95-99.7 rule, what percentage of students failed to earn a grade of at least “c”?

If tan2a=cot(a+60), find the value of a, where 2a is an acute angle

Ofin . (2,4) (2,1) a. y= 2 b. x= 2 c. x= -2 d. y= 2x