# Free Introduction to Graphs 01 Practice Test - 8th Grade

Students in Mrs. Smeera's class were surveyed about snacks and asked to choose one snack they liked most from a list. The bar graph below summarizes the data collected from this survey.

Assuming that one student likes only one of the given snacks, ___ percentage of students liked mixture.

#### SOLUTION

Solution :

The total number of students are 22. The number of students who like the mixture is 2. The percentage of students who like mixture is 222×100 = 9.1%.

From the graph identify the fruit that has same sales on both Monday and Tuesday.

A.

Mango

B.

Apple

C.

Orange

D.

Papaya

#### SOLUTION

Solution : D

The graph depicts the sales of each fruit on Monday and Tuesday. The height of the bars quantify the sales for that particular fruit on these days. We need to look for the fruit which has the same bar height corresponding to Monday and Tuesday.

We can see that papaya has sales of 22.5 kg on both Monday and Tuesday.

Using the graph find how many of the fruit/ fruits have more sales on Monday than Tuesday.

A.

0

B.

1

C.

2

D.

3

#### SOLUTION

Solution : B

The height of the bars quantify the sales for that particular fruit on Monday and Tuesday. We need to look for the fruits for which the bars corresponding to Monday have more height than those for Tuesday.

We can see that banana is the only fruit for which sales on Monday is more than that on Tuesday.

For the given data set, you wish to make a histogram. What will be the width of each bar, given that 1kg is 2 units in the x axis?

Weights(Kg)No. of persons404544550125055135560660655

A.

5

B.

10

C.

15

D.

20

#### SOLUTION

Solution : B

The width of the bar should be equivalent to 5 kg since this is the class interval. But 1 kg equates to 2 units in the x-axis. Hence the width of each bar is 5 × 2 = 10 units.

The line graph below shows people in a store at various times of the day. How many people are there in the store at 2:30 pm?

A.

12

B.

17

C.

10

D.

15

#### SOLUTION

Solution : C

In the figure, the x-axis represents the time and y-axis represents the number of people. In a line graph, the value of datum at any point can be found using the line. The time 2:30 pm is exactly halfway between 2 and 3 pm. The number of people is on the y-axis corresponding to the point between that at 2 and 3. Halfway between 5 and 15 on a number line is 10. Hence the number of people at 2:30 pm are 10.

If we take regular data readings at small time intervals, what type of graph is most suitable?

A.

Histogram

B.

Line graph

C.

Single bar graph

D.

Double bar graph

#### SOLUTION

Solution : B

A line graph is most suitable if we take regular readings at small time intervals. Using the given intermediate points, readings can be estimated at any given time in the period.

Plot the line graph for this data. Which of the following statement is true?

Sarah brought a new car in 2001 for ₹8,00,000. The value of her car changed each year as shown in the table below.
(Values of Sarahs car)YearValue20018,00,00020027,50,00020036,60,00020045,80,00020054,80,00020063,30,00020071,90,000

A.

All the points lie on a common straght line

B.

The sale value of car is always reducing with time

C.

In 2004 the car had a higher sale value than 2002 but lower than 2006

D.

Data Insufficient.

#### SOLUTION

Solution : B

The graph is as shown above. From this line graph it can be seen that the value of the car keeps reducing with time.

In a two-dimensional plane, how many pieces of data do we need to locate a point ___?

#### SOLUTION

Solution :

We need two pieces of data to represent any point on a two-dimensional plane. The position of any point in two-dimensional space is given by an ordered pair of real numbers, each number giving the distance of that point from the origin measured along the given axis, which is equal to the distance of that point from the other axis.​

The coordinates of the point A of the square ABCD are (4, 3).

A.

True

B.

False

#### SOLUTION

Solution : B

The x-axis point of A = 3

The y-axis point of A = 4

Hence, the coordinates of point A = (3, 4)

The graph shows the distribution of TV viewership for TV channels in the year 2012-13. The % distribution for entertainment is ___

A.

30%

B.

40%

C.

50%

D.

60%

#### SOLUTION

Solution : C

The sum of the percentages of all parts of a pie chart should add up to 100. The sum of percentages of types of channels other than entertainment adds up to 25 + 15 + 10 = 50%. Hence the remaining % for entertainment is 50%.