Answer:
First one equals -15
Second one equals -3
Step-by-step explanation:
(-4)*2 - 7
= (-8) - 7
= (-15)
(-4) + 1
= (-3)
Hopefully this helps.
8 2/5 ÷(-2 1/5) = -3.81818181818
Answer:
7 6/7
Step-by-step explanation:
×
=
×
=
=
Answer:
Exactly 16%.
Step-by-step explanation:
Normal Probability Distribution
Problems of normal distributions can be solved using the z-score formula.
In a set with mean
and standard deviation
, the z-score 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 p-value, we get the probability that the value of the measure is greater than X.
The mean of a certain set of measurements is 27 with a standard deviation of 14.
This means that 
The proportion of measurements that is less than 13 is
This is the p-value of Z when X = 13, so:

has a p-value of 0.16, and thus, the probability is: Exactly 16%.