Mrs. Smith's class is working on a variety of science experiments. Each

Mathematics

1 answer:

SVETLANKA909090 [29]3 years ago

8 0

Answer:

Step-by-step explanation:

If there are <em>n</em> students, then the number of pairs is $\frac{n(n-1)}{2}$ .

With 12 students, $\frac{12(12-1)}{2} = \frac{132}{2}=66$ pairs can be formed.

The reason the formula works is this: Each of the 12 students can be paired with 11 other students (no student is paired with him/her self). But counting 12 x 11 = 132 counts each pair <u>twice</u>. Example: student A can be paired with student B,..., student B can be paired with student A. The pair was counted two times.

See the attached image that shows pairings of 5 students. There are

5(5 - 1)/2 = 5(4)/2 = 10 pairs.

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Jamie is walking her neighbors’ dog while they are away. She is keeping track of the total number of blocks she walks over time.

Bumek [7]

Answer:

C. Yes, because the ratios are equivalent between each pair of values.

Step-by-step explanation:

A relationship between two quantities is proportional if the ratio of the two quantities are the same for all the given possible pairs of values.

In the table given, the ratio of block to mins in the first given pair of values is 3/6 = 3/6 = ½.

In the second given pair, it is 7 to 14 = 7/14 = ½. The same ratio is gotten for the others as well.

Therefore, the table represents a proportional relationship.

The answer is: "C. Yes, because the ratios are equivalent between each pair of values."

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3 years ago

Elena notices that when she spends less time on social media the night before a quiz, she gets a higher score. Before one quiz,

MatroZZZ [7]

Answer:

$f(x) = -\dfrac{2}{17}x + \dfrac{843}{17}$

Step-by-step explanation:

Given:

Score of 37 with 107 minutes on social media.

Score of 41 with 73 minutes on social media.

The two pieces of information above can be thought of as two points on a line. Since the quiz score is a function of the number of minutes on social medial, let the number of minutes on social media be x and the score be y. The given information gives us two ordered pairs: (107, 37) and (73, 41).

Now we need to write the equation of a line that passes through these two points.

The two-point form of the equation of a line is:

$y - y_1 = \dfrac{y_2 - y_1}{x_2 - x_1}(x - x_1)$