Given the total number of students are 180, the mean of data is 88g, and standard deviation is 1g.
A normal curve is a bell-shaped curve with symmetry about the mean and it spreads uniformly on both sides (left side and right side) of the mean.
The empirical rule is also called "68-95-99.7" rule. It says that :-
A) 68% of the data values fall between 1 standard deviation about mean (34% on left side and 34% on right side),
B) 95% of the data values fall between 2 standard deviations about mean (47.5% on left side and 47.5% on right side), and
C) 99.7% of the data values fall between 3 standard deviations about mean (49.85% on left side and 49.85% on right side).
According to distribution of normal curve and "68-95-99.7" empirical rule, we can say 49.85% of data values are above the mean within 3 standard deviations.
So it means 49.85% of total students report readings more than 88g.
Number of students reporting readings more than 88g = 49.85% of 180 = 0.4985 × 180 = 89.73
Hence, approximately 89 students report readings more than mean value.
Answer:
<u>-4 < x < -2</u>
Step-by-step explanation:
Taking the left part of the inequality :
Taking the right part of the inequality :
Solution :
Answer:
B
Step-by-step explanation:
Since the inequality sign is greater than or equal to, we need a solid line with the color filled at the top of the graph. This already eliminates answer choice A or D.
Since we know it has to have a solid line, the answer is B.
Its pretty simple
9x-7y = 22
x + 3y = -24
(9x-7y = 22)
-9(x + 3y = -24)
= -9x -27y = 216
+ 9x-7y = 22
= -34y = 238
= / -34 = 238/-34
y = -7
now plug -7 in one of the equation
x + 3(-7) = -24
x -21 = -24
+21. +21
x = -3
so answer is x = -3 and y = -7
