Mariana averaged 80 on her first three math exams. The first score was 86. The second score was 74. What was the third exam scor
1 answer:
The three scores are 86, 74, and an unknown score x. The average (i.e. the sum divided by how many there are) is 80, so we have
Multiply both sides by 3 and you get
Subtract 160 from both sides to get
Note: you could solve this exercise very quickly if you notice that the two numbers, 86 and 74, are symmetrical with respect to 80, which is the average. So, the third number must be the average.
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The vendor has to sell 88 gingerbread houses to earn a profit of $665.60 and there is no chance that the vendor will earn $1500.
Given an equation showing profits of A Christmas vendor as
P=-0.1+30g-1200.
We have to find the number of gingerbread houses that the vendor needs to sell in order to earn profit of $665.60 and $1500.
To find the number of gingerbread houses we have to put P=665.60 in the equation given which shows the profit earned by vendor.
665.60=-0.1+30g-1200
0.1-30g+1200+665.60=0
0.1-30g+1865.60=0
Divide the above equation by 0.1.
-300g+18656=0
Solving for g we get,
g=[300±]/2*1
g=[300±
g=[300±]/2
g=(300±124)/2
g=(300+124)/2 , g=(300-124)/2
g=424/2, g=176/2
g=212,88
Because 212 is much greater than 88 so vendor prefers to choose selling of 88 gingerbread houses.
Put the value of P=1500 in equation P=-0.1+30g-1200.
-0.1+30g-1200=1500
0.1-30g+1500+1200=0
0.1-30g+2700=0
Dividing equation by 0.1.
-300g+27000=0
Solving the equation for finding value of g.
g=[300±]/2*1
=[300±
=[300±]/2
Because comes out with an imaginary number so it cannot be solved for the number of gingerbread houses.
Hence the vendor has to sell 88 gingerbread houses to earn a profit of $665.60 and there is no chance that the vendor will earn $1500.
Learn more about equation at brainly.com/question/2972832
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Answer: Options 'C' and 'E' are correct.
Step-by-step explanation:
Since we have given that
Quantity of snowfall in February at Delphine's house be f centimeters
Quantity of snowfall in March at Delphine's house be 40% more than in February.
According to question,
So, Options 'C' and 'E' are correct.
i.e. C) 1.4f
E)
Call the parabola 
, parameterized by 
with 
. Then the work done by 
along is
