(Measures of Center) Is the pace of life slower in smaller cities?

• Does it take less time to get to work in smaller cities? Here are the travel times in
minutes for 15 workers in North Carolina, chosen at random by the Census Bureau along with a dotplot of the data:

30 20 10 40 25 20 10 60 15 40 5 30 12 10 10
•••
5 10 15 20 25 30 35 40 45 50 55 60

Travel time to work (minutes)

1. Find the median

The median is __A__

About __B__ of the travel times are less than the median and about __C__
are greater.

2. Calculate the mean travel time.

The mean of __D__
is the __E__
travel time to work.

3. Which measure of center - the median or the mean - describes the typical travel time to work for this sample of workers in North Carolina.

The __F__ best describes the typical travel time to work because the distribution is skewed right.

step-by-step explanation:

30% of $420 is 0.30($420) = $126 and $420 + $126 = $546.

or, 130% of $420 is 1.3($420) = $546.

notice that this is not the $600 original list price with which we started.

why doesn't this work?

the method does not work because 30% of $420 is not the same amount as the 30% of $600. it may seem obvious when stated this way, but it is a very common error made on problems of this type. we cannot just use the same percent and get back to the original amount because we are taking that percent of a different value.

to work problems of this type correctly, it is generally best to write an equation for the situation and then solve.

example: since (100% – 30%)(original price) = (sale price)

70% of the   (original price) is $420.

0.7x   = 420

equation image indicator

x = 600

the original cost was $600.

we may also solve this problem using the two-step method. working the problem in two steps requires us to use more algebra skills. we have to know that x = 1x (identity property of multiplicationtext annotation indicator) and that 1x – 0.3x = 0.7x (subtracting like terms). then we solve the problem as follows:

(original price) – 30%(original price) = sale price

x – 0.3x = 420

0.7x = $420

equation image indicator

x = 600

the original cost was $600.  

note that with both of the above methods we do obtain the correct original amount.

example: after a 5% pay raise, hermione is earning $22,680 per year. what was she earning before the pay raise?

105% of (original salary) = current salary

1.05x = 22,680

equation image indicator

x = 21,600

hermione earned $21,600 per year before the pay raise.

this is an example so maybe you will get how to at least do it!

25% is the answer

slope= 1

y-inter slope= 0

x       y

o     0

1       1

2     2

ect.

step-by-step explanation: