Answer:
a2 + a - 20
(a + 5) (a-4)
a2 - 9a + 20
(a-5) (a-4)
a2 - 8a - 20
(a-10) (a + 2)
a2 - 12a + 20
(a-10) (a-2)
a2 - 19a - 20
(a-20) (a + 1)
Step-by-step explanation:
Answer:
The z-score of 90 is 1.35
Step-by-step explanation:
The z-score is calculated using the formula:
From the question, it was given that the mean is
and the standard deviation is
and x=90.
We substitute the given values to obtain:
Answer:
1.35
Step-by-step explanation:
Answer:
32.2
Step-by-step explanation:
The given data set is:
56,78,123,34,67,91,20
The mean of this data set is
The standard deviation is given by;