4(3+5) --> this means that 12/4=3 and 20/4=5 and 4 is the GCF
Answer:
86%
Step-by-step explanation:
Let g represent the mean mark for the 10 girls in the class. Then the mean mark for the class was ...
10g +20(62%) = 30(70%)
g = 3(.7) -2(.62) . . . . . . . . . divide by 10 and subtract 2(.62)
g = .86 = 86%
The mean mark for girls was 86%.
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You can do this in your head if you consider it in terms of deviations from the mean. The second equation above can be rewritten and factored as ...
g = 70% +2(70% -62%)
That is, because there are 2 boys for every girl, the girl's score is above the mean by an amount that is 2 times the amount that the boy's score is below the mean. The boys' score is below by 8%, so the girls' score is above by 16%, so is 86%.
Answer:
<h2><u>E</u><u>k</u>sponent</h2>
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![= \sqrt[3]{ {2}^{4} }](https://tex.z-dn.net/?f=%20%3D%20%20%5Csqrt%5B3%5D%7B%20%7B2%7D%5E%7B4%7D%20%7D%20)
![= \sqrt[3]{2 \times 2 \times 2 \times 2}](https://tex.z-dn.net/?f=%20%3D%20%20%20%5Csqrt%5B3%5D%7B2%20%5Ctimes%202%20%5Ctimes%202%20%5Ctimes%202%7D%20)
![= \boxed {\bold{\sqrt[3]{16}(c.) }}](https://tex.z-dn.net/?f=%20%3D%20%20%20%5Cboxed%20%20%7B%5Cbold%7B%5Csqrt%5B3%5D%7B16%7D%28c.%29%20%7D%7D)
Answer:
54.8
Step-by-step explanation:
Pythagorean theorem is a^2+b^2=c^2.
Plug the given values in to get 61^2+b^2=82^2
61^2 is 3,721 and 82^2 is 6,724.
6,724-3,721 is 3,003.
The square root of 3,003, rounded to a reasonable value, is 54.8.
The length of AC is 54.8.
