Answer:
26320
Step-by-step explanation:
X x_ = (13+14+11+11+13+10)/6=12 x-x_ (x-x_)^2 standard deviation is
13 for all X_ it is the same 13-12=1 . 1. =(12/6)^1/2=1.41421
14 14-12=2 . 4.
11 11-12=-1 . 1.
11 11-12 =-1 . 1.
13 13-12=1 . 1.
10 10-12=-2. 4.
Y=5x+30
X is the days
And so by plugging in x you get
y=5(5)+30
y=25+30
y=55
And so by day 5 she's running 55 minutes
But that's what I think
Answer:
The correct answer is: The test had 10 4-point questions and 30 3-point questions.
Step-by-step explanation:
Let t be the number of 3-point questions on the test
and
f be the number of 4-point questions on the test
Then,
According to the given statement that the test had 40 problems
Eqn 1
And
According to given statement that the total points are 130
Eqn 2
These equations form a system of linear equations in two variables.
Elimination method or substitution method can be used to solve the system.
So, from equation 1:
![t+f = 40\\t = 40-f](https://tex.z-dn.net/?f=t%2Bf%20%3D%2040%5C%5Ct%20%3D%2040-f)
Putting t = 40-f in equation 2
![3(40-f) +4f = 130\\120-3f+4f = 130\\](https://tex.z-dn.net/?f=3%2840-f%29%20%2B4f%20%3D%20130%5C%5C120-3f%2B4f%20%3D%20130%5C%5C)
Subtracting 120 from both sides
![120-3f+4f-120 = 130-120\\f = 10](https://tex.z-dn.net/?f=120-3f%2B4f-120%20%3D%20130-120%5C%5Cf%20%3D%2010)
Putting f = 10 in equation 1
![t+10 = 40](https://tex.z-dn.net/?f=t%2B10%20%3D%2040)
Subtracting 10 from both sides
![t+10-10 = 40-10\\t = 30](https://tex.z-dn.net/?f=t%2B10-10%20%3D%2040-10%5C%5Ct%20%3D%2030)
Hence,
Number of 3-point questions = t = 30
Number of 4-point questions = f = 10
So,
The correct answer is: The test had 10 4-point questions and 30 3-point questions.
Answer:
The correct answer by solving with the System of Inequalities is ![-4\leq x](https://tex.z-dn.net/?f=-4%5Cleq%20x%3C4)
Step-by-step explanation: