In Ms. Miller's English class, students are given five tests in a semester. At the end of the semester, the scores that a student has earned on the five tests are averaged to obtain that student's class average. So far, DeShawn has taken the first four tests, and his scores are 71%, 90%, 82%, and 77%. Which of the following is the range of all the class averages that DeShawn could possibly receive at the end of the semester?

The options are;

A. 64 - 84%

B. 64 - 100%

C. 80 - 84%

D. 80 - 100%

Option A: 64% - 84%

Step-by-step explanation:

We are told his scores on the five tests are averaged to obtain that student's class average.

Now, we are only given 4 of the scores which are; 71%, 90%, 82%, and 77%.

Now, maximum value of the 5th score will be 100% while the minimum value of the 5th score will be 0%

Thus,to find the range of the average score, we will find the average with the maximum 5th score and the minimum 5th score.

With maximum 5th score of 100%, we have an average of;

(71% + 90% + 82% + 77% + 100%)/5 = 420%/5 = 84%

With minimum 5th score of 0%, we have an average of;

(71% + 90% + 82% + 77% + 0%)/5 = 320%/5 = 64%

Thus, the range of all the class averages is; 64% - 84%

answer-

the equation that models this pattern is

solution-

a researcher placed a petri dish with 32,000 bacterial cells. one hour after being placed in the vacuum chamber, the number of cells in the petri dish had halved. another hour later, the number of cells had again halved.

this can be represented as exponential decreasing function,

where,

putting the values,

y-intercept means, where x=0, so

the coordinate of this poin will be (0, 32000)

this means when x=0 or at the starting of the research, the number of bacteria cells was 32000.

after 3 hours, number of bacteria cells will be,

the   coordinate of this point will be (3, 4000)