Answer:
a) Scores of 2 and higher are significantly high
b) Scores of -2 and lower are significantly low
c) Scores between -2 and 2 are not significant.
Step-by-step explanation:
Mean = 0
Standard deviation = 1
a. significantly high (or at least 2 standard deviations above the mean).
2 standard deviations above the mean is:
0 + 1*2 = 2
So scores of 2 and higher are significantly high
b. significantly low (or at least 2 standard deviations below the mean).
2 standard deviations below the mean is:
0 - 1*2 = -2
So scores of -2 and lower are significantly low
c. not significant (or less than 2 standard deviations away from the mean).
2 standard deviations above the mean is:
0 + 1*2 = 2
2 standard deviations below the mean is:
0 - 1*2 = -2
So scores between -2 and 2 are not significant.
Answer:
a. A minimum of 300
Step-by-step explanation:
If her bill is $142 then it is a sum of the flat rate plus the money she pays for all the smses she sent. As an equation, it can be expressed this way
106 + 0.12x = 142 where x is the number of smses
0.12x = 36
x = 300 smses
So if we were told that she pays $142 per month, we'd know that she sends 300 smses. But we are told she pays AT LEAST $142 so there is a possibility that she sends even more than 300 smses