141k views
2 votes
The table displays the frequency of scores for a calculus class on an exam. The mean of the exam scores is 3.5. Score 1 2 3 4 5 Frequency 1 3 f 13 4 a. What is the value of f in the​ table? b. What is the mode of all the exam​ scores? c. What is the median of all the exam​ scores?

1 Answer

5 votes

Answer:

f=11

Mode=4

Median=4

Step-by-step explanation:

We are given that

a.Mean of the exam score,
\bar x=3.5

Score(x) frequency C.F

1 1 1

2 3 4

3 f 15(4+f=4+11)

4 13 28

5 4 32


\sum f_i=1+3+f+13+4=21+f


\sum f_ix_i=1(1)+2(3)+3(f)+4(13)+5(4)=1+6+3f+52+20=79+3f


(\bar x)=(\sum f_ix_i)/(\sum f_i)

Using the formula


3.5=(79+3f)/(21+f)


73.5+3.5f=79+3f


3.5f-3f=79-73.5


0.5f=5.5


f=(5.5)/(0.5)=11

b.Mode:The number which is repeat most times .

4 repeat most times

Hence, mode of all exam scores=4

N=32

N is even


Median=(((n)/(2))^(th)+((n)/(2)+1)^(th))/(2)

Median=
(16th+17th)/(2)=(4+4)/(2)=(8)/(2)=4

User Alex Alifimoff
by
8.2k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories