Assuming the exams have equal weight it would be a straight average of the four tests.
Let n be the required score on the last test:
(82 + 64 + 98 + n) / 4 ≥ 70
Now you need to solve for n. Start by multiplying through by 4 on both sides:
82 + 64 + 98 + n ≥ 280
Now add up the numbers on the left:
244 + n ≥ 280
Now subtract 244 from both sides:
n ≥ 36
The student must score a 36 or better on the final exam... seems pretty doable given her prior scores.
2006-12-08 12:20:18
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answer #1
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answered by Puzzling 7
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Remember that the average of 4 tests is calculated with the following:
(T1 + T2 + T3 + T4)/4 = A
Where A is the average and T1 through T4 are the scores.
Since she needs at least 70, and we know what T1 through T3 equal, then
(82 + 64 + 98 + T4)/4 >= 70
Translation: The average of her test scores must be greater than or equal to 70. Now we solve this as if it were an equation.
(244 + T4)/4 >= 70
(244 + T4) >= 280
T4 >= 36
Therefore, she must get at least 36 to receive credit for the course on her fourth test.
Let's check:
(T1 + T2 + T3 + T4)/4 = (82 + 64 + 98 + 36)/4 = 70
2006-12-08 12:27:14
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answer #2
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answered by Puggy 7
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82+64+98+X = 70x4
244+X = 280
X=36
2006-12-08 12:27:33
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answer #3
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answered by bill45310252 5
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X = The minimum score we need in the last exam
Step 1: 82/4+64/4+98/4+X/4 = 70
Step 2: 244+ X = 280
Step 3 : X = 36 !
:-)
2006-12-08 12:26:12
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answer #4
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answered by Tal Z 1
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82+64+98=244 so they will need to get a score over fourty and they will be fine they will get an average of a 70 or high if the score above 40
2006-12-08 12:26:22
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answer #5
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answered by God R 3
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(82+64+98+x)/4>=70
2006-12-08 12:30:12
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answer #6
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answered by Anonymous
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(82 + 64 + 98+ x)/4 >= 70
x >= 36
2006-12-08 12:23:42
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answer #7
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answered by Anonymous
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sum must be greater than 280.
Therefore,
x+82+64+98>=280
Therefore x>=36
2006-12-08 12:21:22
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answer #8
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answered by bkc99xx 6
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suppose that the mark she has to get = x
so
(82 + 64 + 98 +x)/4 ≥ 70................*4
224 + x ≥ 280
x ≥ 280 -224
x ≥ 36
so she must get 36 or more
2006-12-08 19:02:04
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answer #9
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answered by M. Abuhelwa 5
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For increasing cubic binomials the final formula is as follows: (a + b) ^ 3 = a^3 + 3*a^2*b^a million + 3*a^a million*b^2 + b^3 on your case, a is x and b is -y^5 So (x - y^5)^3 = x^3 + 3*x^2*(-y^5)^a million + 3*x^a million*(-y^5)^2 + (-y^5)^3 Simplified: =x^3 - 3x^2*y^5 + 3x*y^10 - y^15 :D
2016-11-30 08:18:50
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answer #10
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answered by ? 4
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