Question

110 adults with gum disease were asked the number of times per week they used to floss before their diagnoses. The (incomplete) results are shown below:

# of times floss per week	Frequency	Relative Frequency	Cumulative Frequency
0			10
1	15	0.1364
2	15	0.1364	40
3	16	0.1455	56
4	14	0.1273	70
5	12	0.1091	82
6	15	0.1364	97
7	13	0.1182	110

a. Complete the table (Use 4 decimal places when applicable)

b. What is the cumulative relative frequency for flossing 7 times per week? %

Answer 1

Ans:

a)Frequency column should sum up to 110.

All given frequences sum upto 100,so missing frequency is will be=110-100=10

Relative frequency coulmn should sum upto 1.

All given relative frequencies sum upto 0.9093,so missing relative frequency will be=1-0.9093=0.0907

cumulative frequency corresponding to 1 times floss per week=10+15=25

b)cumulative relative frequency for flossing 7 times per week=1 or 100%

# of times floss per week	Frequency	Relative Frequency	Cumulative Frequency	cumulative relative Frequency
0	10	0.0907	10	0.0907
1	15	0.1364	25	0.2271
2	15	0.1364	40	0.3635
3	16	0.1455	56	0.509
4	14	0.1273	70	0.6363
5	12	0.1091	82	0.7454
6	15	0.1364	97	0.8818
7	13	0.1182	110	1