just multiply 45 time 31!
Answer:
8
Step-by-step explanation:
x=pizza
y= breadsticks
3x+2y=30
2x+3y=25
first we myltiply the top equation with 3 and then w emultiply the lower equation with -2 so it is
9x+6y=90
-4x-6y= -50
now we can add them together and the y contracts
5x=40
now we divide it by 5
x=8
So pizza costs 8
Step-by-step explanation:
m=y2-y1/x2-x1
m=0-(-2)/4-2
m=2/2
m=1
Answer:
Where
and
Then we have:
With the following parameters:


Step-by-step explanation:
Previous concepts
Normal distribution, is a "probability distribution that is symmetric about the mean, showing that data near the mean are more frequent in occurrence than data far from the mean".
The Z-score is "a numerical measurement used in statistics of a value's relationship to the mean (average) of a group of values, measured in terms of standard deviations from the mean".
Solution to the problem
Let X the random variable that represent the number of cars running a red light of a population, and for this case we know the distribution for X is given by:
Where
and
Since the distribution for X is normal then we know that the distribution for the sample mean
is given by:
With the following parameters:


Answer:
1/3 min ( = 20 seconds)
Step-by-step explanation:
The period of the ride is the time he takes to complete 1 revolution
We are given:
12 revolutions -------> takes 4 min
1 revolution ------> takes 4/12 = 1/3 min (= 20 seconds)