Fred and his family went to the zoo. Fred started the day with $100. He bought 2 adult tickets for

The frequency distributions of two data sets are shown in the dot plots below.

fredd [130]

Answer:

1st, 4th and 6th statements are true.

Step-by-step explanation:

We have been given two dot-plots and we are asked to select all the true statements about given dot plots.

Let us write all the data points of both dot plots.

Data set 1:

1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 4, 4, 7.

Data set 2:

1, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 4, 4.

1. The mean of data set 1 is greater than the mean of data set 2.

Let us find mean of both data sets.

$\text{Mean of data set 1}=\frac{1+1+1+1+1+2+2+2+2+2+2+2+2+3+3+3+4+4+7}{19}$

$\text{Mean of data set 1}=\frac{45}{19}$

$\text{Mean of data set 1}=2.3684\approx 2.37$

$\text{Mean of data set 2}=\frac{1+1+1+1+1+2+2+2+2+2+2+2+2+3+3+3+4+4}{18}$

$\text{Mean of data set 2}=\frac{38}{18}$

$\text{Mean of data set 2}=2.11$

We can see that mean of data set 1 is greater than mean of data set 2, therefore, 1st statement is true.

2. The mean of data set 1 is equal to the mean of data set 2.

Since mean of data set 1 is greater than mean of data set 2, therefore, 2nd statement is false.

3. The median of data set 1 is greater than the median of data set 2.

Since data set 1 has 19 data points, so median of data set 1 will be value of 10th data set, that is 2.

Our data set 2 has 18 data points, so median of data set 2 will be the average of 9th and 10th data points.

$\text{Median of data set 2}=\frac{2+2}{2}$

$\text{Median of data set 2}=\frac{4}{2}=2$

Since median of data set 2 is also 2, therefore, 3rd statement is not true.

4. The median of data set 1 is equal to the median of data set 2.

Since both data set's median is 2, therefore, 4th statement is true.

5. The standard deviation of data set 1 is smaller than the standard deviation of data set 2.

Using online SD calculator we get SD of data set 1 is 1.422 and SD of data set 2 is 0.936. Since 1.422 is greater than 0.936, therefore, 5th statement is false.

6. The data sets have the same interquartile range.

$Q_1\text{ of data set 1}=1$

$Q_3\text{ of data set 1}=3$

$\text{IQR of data set 1}=3-1=2$

$Q_1\text{ of data set 2}=1$

$Q_3\text{ of data set 2}=3$

$\text{IQR of data set 2}=3-1=2$

Since both data set's IQR is 2, therefore, 6th statement is true.

3 0

4 years ago

Read 2 more answers

How many integers n leave remainder 4 when divided by 7, if n satisfies the given inequality?

bekas [8.4K]

Consider inequality $|-n|$ This inequality is equivalent to inequality $|n|$

This means that $-46$

The greatest integer number n, such that $-46$ when dividing by 7 gives the remainder 4 is 39. Then subtract 7, you get 32, then 25 and so on.

When n=-39, -32, -25, -18, -11, -4, 4, 11, 18, 25, 32, 39 then dividing by 7 the remainder is 4.

Answer: 12 integers.

4 0

3 years ago

Thu gọn biểu thức : (x-5)(x+5)-(x+1)^2

Kipish [7]

$(x-5)(x+5)-(x+1)^2\\=x^2 -25-(x^2+2x +1)\\=x^2 -25-x^2-2x -1\\=-2x-26$

ANSWER: -2x -26

Ok done. Thank to me :3

5 0

1 year ago

What is the probability of rolling doubles and a sum of 6

alisha [4.7K]

3/6 look at the pic to understand

4 0

3 years ago

Please help me! 15 points

arsen [322]

Answer:

a. The length of FA is 1.

b. The length of the radius (AC) is 2.

c. The circumference of the circle A is 4π units.

d. The measure of the minor arc BC is 107°.

e. The length of the minor arc BC is (107/90) π.

f. The m<BFC and m<EFD is 125.5°.

g. The m<BFE is 180°.

Step-by-step explanation:

Radius: R=AB=2

FC=1

Arc CD = 180°

Minor arc BD = 73°

Minor arc EC = 36°

a. What is the length of FA?

FA=AC-FC

AC is a radius, then AC=AB→AC=2

Replacing in the known values in the equation above:

FA=2-1

FA=1

b. What is the length of the radius (AC)?

The radius AC must be equal to the radius AB, then:

AC=AB→AC=2

c. What is the circumference of the circle A?

Circunference of circle A: L=?

L=2 π R

L=2 π (2)

L=4π

d. What is the measure of the minor arc BC?

Minor arc BC = arc CD - Minor arc BD

Minor arc BC = 180°-73°

Minor arc BC = 107°

e. What is the length of the minor arc BC?

Length of minor arc BC: l=?

l=(Minor arc BC / 360°) L

l=(107°/360°) 4π

l=(4*107/360) π

l=(107/90) π

f. What is the m<BFC and m<EFD

<BFC and <EFD are interior angles, then:

m<BFC = m<EFD = ( Minor arc BC + Minor arc DE) / 2

Minor arc DE = arc CD - Minor arc EC

Minor arc DE = 180°-36°

Minor arc DE = 144°

m<BFC = m<EFD = ( 107° + 144° ) / 2

m<BFC = m<EFD = ( 251° ) / 2

m<BFC = m<EFD = 125.5°

g. What is the m<BFE?

<BFE is a straight angle, then m<BFE=180°

8 0

3 years ago