Samantha and luis are attempting to determine how many library books each seventh grade student checks out at the same time. samantha surveys every other seventh grade student leaving the library. she samples a total of 40 of the 200 seventh graders. luis samples 30 of the 200 seventh grade students at random in the school cafeteria. whose sample is the most random? luis because his sample is taken from the population of all seventh graders luis because he samples fewer students samantha because she samples more students samantha because her sample is taken from the population of students who use the library

Luis, because his sample is taken from the population of all seventh graders. However, Samanthan has the advantage of having a bigger sample, and that makes it more representative.

Step-by-step explanation:

Taking the sample of the library as Samantha did, is biased, because most of the students there is checking a book, and the aim of the study is not only the ones that use the library, but in general the seventh grade students.

9 x 8 divided by (5-3)=36

, and

for

step-by-step explanation:

we can analyze the pattern at which the terms increase. let us denote , , , so that we can call

note the following:

the pattern: to get the next term value, we just add the next term number (e.g. 1st, 2nd, to the previous term value (term values are the given numbers in the question, 1, 3, 6, 10, 15,

from , to get to , we add

from , to get to , we add

etc.

we need to form a recursive formula, a formula that has the next term as a function of the previous term. so a possible recursive formula can be

, and for