Answer:
And we can find this probability using excel or the normal standard tabe and we got:
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 temperatures of a population, and for this case we know the distribution for X is given by:
Where 
and 
We are interested on this probability
And 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 we can find this probability using excel or the normal standard tabe and we got:
The total revenue that is gained from the sales of the cakes is determined by multiplying the number of cakes by the price. If we let x be the number of $1 that should be deducted from the price and y be the total revenue,
y = (25 - x)(100 + 5x)
Simplifying,
y = 2500 + 25x - 5x²
We get the value of x that will give us the maximum revenue by differentiating the equation and equating the differential to zero.
dy/dx = 0 = 25 - 10x
The value of x is 2.5.
The price of the cake should be 25 - 2.5 = 22.5.
Thus, the price of the cake that will give the maximum potential revenue is $22.5.
We are going to make simultaneous equations.
x will be our $3 ice cream and y will be our $5 ice cream
Equation1 ---- x + y = 50 (the sum of all the ice creams they sell)
Equation 2 ---- 3x + 5y = 180 Sum of all the $3 and $5 ice creams is $180
Since we can't solve for both variables we will put one of the variables in terms of the other.
Take x+y=50 and subtract y from both sides. (I could have done subtracted x - it did not matter). Now we have x= ₋ y +50 (negative y +50)
Now I am going to take equation 2 and replace the x with -y +50
3 (-y +50) + 5y = 180
Now I will use the distributive law on the 3 and what's in the parentheses:
-3y + 150 + 5y = 180
Now I will combine like terms (the -3y and the 5y)
2y + 150 = 180
Now subtract 150 from both sides of the equation
2y = 30
Divide both sides by 2
and get y= 15 They sold 15 ice creams that cost $5 each
Since equation 1 is x+y=50 we can replace y with 15
x + 15 = 50 Now subtract 15 from both sides x = 35
Since x represents the $3 ice creams, they sold 35 of those.
Check:
35 X 3 = $105
15 x 5 = + <u>75
</u> $180
Answer:
Step-by-step explanation:
a) For a prime numbers we have array with 2 rectangulars R1: a=1 and b=prime number; R2: a=prime number and b=1. Both has the same are, that prime number.
b) For a composite number which are not square number we have rectanular array with even numbers of ractangulars. For example, number 6.
R1: a=1,b=6; R2: a=2,b=3; R3: a=3, b=2; R4: a=6,b=1. Each rectangular has the same area, 6.
c) The square number we alway have te odd number of rectanulars, because of the square a=x,b=x can not be simetric. For example 16.
R1: a=1,b=16; R2: a=2 , b=8; R3: a=4,b=4; R4: a=8, b=2; R5:a=16,b=1.Each rectangular has the same area, 16.
