Answer:
The number of students who scored more than 90 points is 750.
Step-by-step explanation:
Quartiles are statistical measures that the divide the data into four groups.
The first quartile (Q₁) indicates that 25% of the observation are less than or equal to Q₁.
The second quartile (Q₂) indicates that 50% of the observation are less than or equal to Q₂.
The third quartile (Q₃) indicates that 75% of the observation are less than or equal to Q₃.
It is provided that the first quartile is at 90 points.
That is, P (X ≤ 90) = 0.25.
The probability that a student scores more than 90 points is:
P (X > 90) = 1 - P (X ≤ 90)
= 1 - 0.25
= 0.75
The number of students who scored more than 90 points is: 1000 × 0.75 = 750.
Answer:
Radius of the convergence is R = 
and,
The Interval of convergence is 
Step-by-step explanation:
Given function : Σ(21x)^k
Now,
Using the ratio test, we have
R = 
or
R = 
or
R = 
now,
for convergence R|x| < 1
Therefore,
< 1
or
and,
Radius of the convergence is R =
and,
The Interval of convergence is
Answer:
The solution for the system of equations is
x=2,y=−2
Explanation:
4x−3y=14.....equation (1)
y=−3x+4.....equation (2)
Solving by substitution
Substituting equation 2 in equation 1
4x−3⋅(−3x+4)=14
4x+9x−12=14
13x=14+12
13x=26
x=2
Finding y by substituting x in equation 1
4x−3y=14
4⋅2−3y=14
8−3y=14
8−14=3y
3y=−6
y=−2
Answer:
y=15/7x-4
Step-by-step explanation:
m=(y2-y1)/(x2-x1)
m=(11-(-4))/(7-0)
m=(11+4)/7
m=15/7
y-y1=m(x-x1)
y-(-4)=15/7(x-0)
y+4=15/7(x)
y+4=15/7x
y=15/7x-4
