Answer: B) 4
Step-by-step explanation:
Using the formula
Standard deviation = √( (Σ ( x - π)²)/n)
To get the standard deviation, first we workout the Mean which is the simple average of the data set
n = 4
(13 + 17 + 9 + 21) / 4 = 60/4 = 15
Mean(x) = 15
Then (x-π)²
13 - 15 = (-2)² = 4
17 - 15 = (2)² = 4
9 - 15 = (-6)² = 36
21 - 15 = (6)² = 36
Σ ( x - π)² = (4 + 4 + 36 + 36) = 80
Standard deviation = √( (Σ ( x - π)²)/n
= √ (80/4)
=√20
= 4.47
= 4
There's not enough given information in the question to calculate an answer.
If we only know that the volume of the box is 96 cm³, then there are an infinite
number of different lengths, widths, and surface areas that it could have.
Let x=red, then blue=2x
x+2x=6
3x=6
x=2
2 red and 4 blue. the odds of drawing a blue is then 4/6, or 2/3, or approximately 66.7%
Notice that 25+23+17+14+12+9=100, so among these students there are no 2 studying 2 subjects.
The probabilities of selecting students studying a certain subject are as follows
P(physics)=25/100
P(chemistry)=17/100
P(maths)=9/100
P(sociology)=23/100
P(political sciences)=14/100
P(anthropology)=12/100
since all the sets are disjoint, that is there are no common elements, and since all the students in consideration are enrolled in one these 6 subjects:
P(physics)+P(chemistry)+P(maths)+P(sociology)+P(political sciences)
+P(anthropology)=1
P(a)=P(sociology)+P(political sciences)+P(anthropology)+P(physics)
thus
P(a')=1-P(a)=P(chemistry)+P(maths)=17/100+9/100=26/100=0.26
Answer: 0.26