Amount of money collected in the 2-day fundraiser is represented by the following equations:
- 12x + 4y = 152 .................. (i)
- 32x + 12y = 420 .................. (ii)
where x is the cost of a chicken lunch and y is the cost of a vegetarian lunch
Multiplying (i) with 3 and subtracting it from (ii)
36x + 12y - (32x + 12y) = 456 - 420
⇒ 4x = 36
⇒ x = 9
Put value of x in (i)
⇒ 12 × 9 + 4y = 152
⇒ 108 + 4y = 152
⇒ 4y = 44
⇒ y = 11
Hence, cost of the vegetarian meal is 11.
Answer:
x=1
Step-by-step explanation:
To get the 7 away, we need to multiply it into the parentheses.
7*-10= -70
7*3=21
-70+21x= -49
Now we combine like terms and we move 70 over. Because we're moving it to the other side of the equation, it becomes positive.
21x= -49+70
-49+70 is the same as 70-49
70-49= 21
Now we put it together.
21x=21
To get the x by itself, we need to divide 21 on both sides.
21x/21= 21/21
21/21=1
x=1
There are 30 adults. Because if there are only three-tenths of adult visitors, you're finding 30% of 100 adult visitors. There are 30 Adults.
Answer:

Step-by-step explanation:
1) 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".
Let X the random variable that represent the GRE score at the University of Pennsylvania for the incoming class of 2016-2017, and for this case we know the distribution for X is given by:
And let
represent the sample mean, the distribution for the sample mean is given by:

On this case 
2) Calculate the probability
We want this probability:

The best way to solve this problem is using the normal standard distribution and the z score given by:

If we apply this formula to our probability we got this:

and rounded would be 0.928