In a survey of 859 homeowners with high-speed internet, the average monthly cost of a high-speed internet plan was $64.1 with standard deviation $12.62. assume the plan costs to be approximately bell-shaped. estimate the number of plans that cost between $51.48 and $76.72. round to the nearest whole number.

68% of the plans cost between $51.48 and $76.72. Of 859, that is 0.68*859 = 584 plans.

Step-by-step explanation:

The Empirical Rule states that, for a normally distributed random variable:

68% of the measures are within 1 standard deviation of the mean.

95% of the measures are within 2 standard deviation of the mean.

99.7% of the measures are within 3 standard deviations of the mean.

In this problem, we have that:

Mean = 64.1

Standard deviation = 12.62

Estimate the number of plans that cost between $51.48 and $76.72.

64.1 - 12.62 = 51.48

So 51.48 is one standard deviation below the mean.

64.1 + 12.62 = 76.72

So 76.72 is one standard deviation above the mean.

By the Empirical Rule, 68% of the plans cost between $51.48 and $76.72. Of 859, that is 0.68*859 = 584 plans.

i think the answer would be c

she will sew have sewn five dresses   and be 1/3 done with the sixth one in an hour.

step-by-step explanation:

3/4 of an hour=45 mins

lucy makes 1 dress per 11.25 minutes

45 mins+11.25 mins=56.25 mins

60 mins- 56.25 mins=3.75 mins

3.75 mins is 1/3 of of 11.25 mins

therefore she the other 1/3 would be part of the hour and she will have sewn 5 dresses and begun the sixth.

contact me if you have any questions you are welcome.