Answer:
Step-by-step explanation:
<u>Given system:</u>
Solve by graphing (see attached).
<u>The solution is the point of intersection of the two lines:</u>
All you have to do is add up all of the sides.
then once you have X, for part 2 all you need to do is replace X with 4 and then solve
Answer:
60 students passed, and 75 appeared in examination.
Step-by-step explanation:
Let's say s is the total number of students and p is the number of students who passed.
80% of the students passed, so:
0.8 s = p
If there were 10 less passers, and 15 less students (5 less failures), then the ratio of passers to failures would be 5/1.
(p − 10) / (s − p − 5) = 5 / 1
Simplify the second equation:
p − 10 = 5 (s − p − 5)
p − 10 = 5s − 5p − 25
6p = 5s − 15
Substitute the first equation.
6 (0.8 s) = 5s − 15
4.8 s = 5s − 15
0.2 s = 15
s = 75
p = 0.8 s
p = 60
60 students passed, and 75 appeared in examination.
we have
Min=26
Q1=67
Q2=80
Q3=87
Max=100
Mean=76
Mode=100
standard deviation=76
IQR=20
so
In this problem
the mean is equal to the standard deviation
therefore
<h2>The standard deviation is incorrectly</h2>