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True [87]
3 years ago
12

Erica wants to know how many books on average are in school libraries in her county. She randomly calls 50 school libraries in h

er county and finds out how many books they have. She adds the number of books together and divides by 50. Her conclusion is there are an average of 18,000 books in a school library. Erica's conclusion is
Mathematics
2 answers:
Rus_ich [418]3 years ago
5 0
<span>valid. She used a representative sample
</span>because she correctly found the average and 18,000 is a reasonable number to get for a the problem
Svet_ta [14]3 years ago
5 0

Answer:

the answer is C. because Even though Erica only called 50 school libraries, this is a sufficient number. Erica’s conclusion is valid. She used a representative sample.

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The length of a rectangle is 2 foot less than 3 times its width. Find the the dimensions of this rectangle if the area is 96 squ
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For example,area = a, length = l, width = w
First we write two equations. The easier equation is the area equation, which we know to be
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l=3w-2\\l=3(6)-2\\l=18-2\\l=16

So "w" = 6 and "l" = 16, and if we multiply them together, we get the correct area, 96. So our dimensions are 6 by 16.
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Help now i have 20 mins!!!!!!!!!!!
IgorLugansk [536]

Answer:

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