(Question 2) I put down 10x=20 then did 10x/10=20/10 then got x=2, what do I do with the M

The number of chocolate chips in an 18-ounce bag of chocolate chip cookies is approximately normally distributed with a mean of 1252 chips and standard deviation 129 chips. (a) what is the probability that a randomly selected bag contains between 1100 and 1500 chocolate chips, inclusive? (b) what is the probability that a randomly selected bag contains fewer than 1125 chocolate chips? (c) what proportion of bags contains more than 1225 chocolate chips? (d) what is the percentile rank of a bag that contains 1425 chocolate chips?

An arc subtends a central angle measuring 7pi/4 radians what fraction of the circumference is this arc?

If p(a) = 0.70 and p(b) = 0.20, then a and b are independent events if