there are three exams in a marking period. A student received grades of 75 and 81 on the first two exams. What grade must the st
udents earn on the last to get an average of no less than 80 for the marking period?
1 answer:
Answer: average means add all scores and divide by number of scores earned
last score is x
so the sum is 75+81+x
3 scores so (75+81+x)/3=average
must be no less than (greater than or equal to 80)
(75+81+x)/3≥80
solve
times both sides by 3 to clear fraction
75+81+x≥240
156+x≥240
minus 156 from both sides
x≥84
the studen must earn at least 84 on last exam
Step-by-step explanation:
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Answer: x=16
Step-by-step explanation:
For this problem, we can set a proportion to find the side length of the smaller rectangle.
[cross multiply]
[divide both sides by 15]
x=16
Width is 11k^2
Length is 5k^3 + 2k^2
Look at: https://www.wyzant.com/resources/answers/392371/what_is_the_length_and_width_of_the_rectangle
C I believe hope this is correct :)
9u+5
9u represents 9 multiplied by a number.
+5 means 5 more than this product.
Hope this helps.
g(x)=2(x-4)
g(x)=20,
20=2(x-4)
20/2=x-4
10=x-4
10+4=x
x=14
