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:
1) 5 2) 6 3) 1.25 or -1.75
Step-by-step explanation:
1. x^2 - 25 = 0
x^2 - 25 = 0
First, add 25 to both sides!
x^2 = 25
Now square root both sides.
x = 5
2. (x-2)^2 = 16
First, square root both sides.
(x-2) = 4
Add 2 on both sides.
(x) = 6
x = 6
3. Quadratic Formula = -b ±
/ 2a
Substitute in:
-6 ±
/ 2(2)
-6±
/ 4
Both forms:
-6 +
/ 4
5 / 4 = 1.25
Negative:
-6 - 1 / 4
-7 / 4 = -1.75
It takes you 45 minutes to clean the fish tank and it takes your sister 30 minutes. how long does it take the two of you working together to clean the fish tank
Answer:
My 1 minute work =
My sisters 1 minute work =
My and My sister's 1 minute work =
=
=
Me and My sister will finish the work in
minutes
Answer:
20 + 2x = 4x
Step-by-step explanation:
So you are setting the two expressions equal to each other.
buying a membership card and paying each time looks like this: 20 + 2x where x is the number of times you go to the gym. 20 dollars base then 2 each time you go.
4 each time you go is just 4x
so just set the two equal to each other.
20 + 2x = 4x
If you solve it you will get x = something, which would be the number of times to make the two equal.
Answer:
no solution to the question