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3 years ago

NEED HELP 20 POINTS !!

Mathematics

1 answer:

goldenfox [79]3 years ago

7 0

Answer:

A. Frame

Step-by-step explanation:

This is because it does not contain the who population and it is the place where the participants of the experiment are selected. It is not the control group because this includes people who were not even in the experiment.

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Eighty percent of the tickets for the baseball game on july 4th been sold. there are 20,000 tickets. how many been sold

Viktor [21]

16000 tickets have been sold.

Glad I could help :)

6 0

3 years ago

What is the rule input numbers are 17 18 _ 28_40

Lelu [443]

19 27 28 29 30 315 64 29 46 is the
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4 0

3 years ago

The sequence$$1,2,1,2,2,1,2,2,2,1,2,2,2,2,1,2,2,2,2,2,1,2,\dots$$consists of $1$'s separated by blocks of $2$'s with $n$ $2$'s i

kicyunya [14]

Consider the lengths of consecutive 1-2 blocks.

block 1 - 1, 2 - length 2

block 2 - 1, 2, 2 - length 3

block 3 - 1, 2, 2, 2 - length 4

block 4 - 1, 2, 2, 2, 2 - length 5

and so on.

Recall the formula for the sum of consecutive positive integers,

$\displaystyle \sum_{i=1}^j i = 1 + 2 + 3 + \cdots + j = \frac{j(j+1)}2 \implies \sum_{i=2}^j = \frac{j(j+1) - 2}2$

Now,

$1234 = \dfrac{j(j+1)-2}2 \implies 2470 = j(j+1) \implies j\approx49.2016$

which means that the 1234th term in the sequence occurs somewhere about 1/5 of the way through the 49th 1-2 block.

In the first 48 blocks, the sequence contains 48 copies of 1 and 1 + 2 + 3 + ... + 47 copies of 2, hence they make up a total of

$\displaystyle \sum_{i=1}^48 1 + \sum_{i=1}^{48} i = 48+\frac{48(48+1)}2 = 1224$

numbers, and their sum is

$\displaystyle \sum_{i=1}^{48} 1 + \sum_{i=1}^{48} 2i = 48 + 48(48+1) = 48\times50 = 2400$

This leaves us with the contribution of the first 10 terms in the 49th block, which consist of one 1 and nine 2s with a sum of $1+9\times2=19$ .

So, the sum of the first 1234 terms in the sequence is 2419.

8 0

2 years ago

Given: 2x^2+3x-5, g(x)=x+9. Find: (fg)(3)

Svetradugi [14.3K]

Answer:

264

Step-by-step explanation:

$f(x)=2x^2+3x-5$

$g(x)=x+9$

$(fg)(x)=f(x) \times g(x)$

$\implies (fg)(x)=(2x^2+3x-5)(x+9)$

$(fg)(3)=(2(3)^2+3(3)-5)(3+9)$

$\implies (fg)(3)=22 \times 12$

$\implies (fg)(3)=264$

8 0

2 years ago

Help plz this is multiple choice so just choose the answer u think is correct.

babymother [125]

the answer is 34.83 I believe

5 0

3 years ago