Step-by-step explanation:
Since we have given that
Total number of members in a sports club = 38
Number of women in the club = 14
Number of women play tennis =10
Number of men play tennis = 8
Since they all play either squash or tennis.
Total number of men in the club is given by
So, number of men playing squash is given by
Number of women playing squash is given by
so, the table is shown below :
Men Women Total
Tennis 16 4 20
Squash 8 10 18
Total 24 14 38
Answer:
At least 75% of these commuting times are between 30 and 110 minutes
Step-by-step explanation:
Chebyshev Theorem
The Chebyshev Theorem can also be applied to non-normal distribution. It states that:
At least 75% of the measures are within 2 standard deviations of the mean.
At least 89% of the measures are within 3 standard deviations of the mean.
An in general terms, the percentage of measures within k standard deviations of the mean is given by .
In this question:
Mean of 70 minutes, standard deviation of 20 minutes.
Since nothing is known about the distribution, we use Chebyshev's Theorem.
What percentage of these commuting times are between 30 and 110 minutes
30 = 70 - 2*20
110 = 70 + 2*20
THis means that 30 and 110 minutes is within 2 standard deviations of the mean, which means that at least 75% of these commuting times are between 30 and 110 minutes