Answer:
0
Step-by-step explanation:
Answer:
14.63% probability that a student scores between 82 and 90
Step-by-step explanation:
Problems of normally distributed samples are solved using the z-score formula.
In a set with mean
and standard deviation
, the zscore of a measure X is given by:

The Z-score measures how many standard deviations the measure is from the mean. After finding the Z-score, we look at the z-score table and find the p-value associated with this z-score. This p-value is the probability that the value of the measure is smaller than X, that is, the percentile of X. Subtracting 1 by the pvalue, we get the probability that the value of the measure is greater than X.
In this problem, we have that:

What is the probability that a student scores between 82 and 90?
This is the pvalue of Z when X = 90 subtracted by the pvalue of Z when X = 82. So
X = 90



has a pvalue of 0.9649
X = 82



has a pvalue of 0.8186
0.9649 - 0.8186 = 0.1463
14.63% probability that a student scores between 82 and 90
The numbers given in the problem above are part of an arithmetic sequence with first and sixth terms equal to -21 and -36, respectively. Firstly, calculate for the common difference (d).
d = (-36 - -21) / (6 - 1) = -3
The arithmetic mean is calculated by adding -3 to the term prior to it.
a2 = -21 + -3 = -24 a3 = -24 + -3 = -27
a4 = -27 + -3 = -30 a5 = -30 + -3 = -33
Thus the four arithmetic means are -24, -27, -30, and -33.
Answer: -0.5c
Step-by-step explanation: multiply -2.5 by 1/5 (0.2) and you get -0/5
Answer: No, they are not.
Step-by-step explanation: To see if ratios are equivalent, you have to simplify them. 6:4 can be simplified to 3:2 but 19:12 cannot be simplified anymore. Since 3:2 is not equal to 19:12, they are not equivalent.