All the solutions provided inÂ **McGraw Hill My Math Grade 3 Answer Key PDF Chapter 12 Review **will give you a clear idea of the concepts.

## McGraw-Hill My Math Grade 3 Chapter 12 Review Answer Key

**Review**

**Vocabulary Check**

**Use the word bank below to complete the crossword puzzle.**

analyze

bar graph

data

interpret

key

line plot

pictograph

scale

survey

tally chart

ACROSS

3. to explain what a graph shows

4. to collect data by asking people the same question

6. a graph that uses bars of different lengths or heights

7. to study data on a graph

DOWN

1. a scaled picture graph

2. tells “how many” each symbol represents

4. a set of numbers that represents the data

5. collected information

Answer:

**Concept Check**

For Exercises 8-13, refer to the table that shows the instrument each student plays.

Question 8.

Record the data in the tally chart.

Answer:

Question 9.

Display the set of data from above in the pictograph below.

Answer:

Question 10.

Display the set of data from the pictograph in the bar graph below.

Answer:

Question 11.

How many students are not playing either a brass or a string instrument?

Answer:

Number of students playing woodwings are 5.

Number of students playing percussion are 7.

Therefore, the number of students not playing either a brass or a string instrument will be the sum of students playing woodwings and percussion, 5+7=12

Question 12.

Hunter is sick today. Miss Miller will practice with half of the students today. How many students will practice with Miss Miller today?

Answer:

Total number of students will be 7+5+4+5=21.If Hunter is sick today, then the total will be 21-1=20 students.

As mentioned above, Miss Miller will practice with half of the students today.

Therefore,the number of students she will practice with will be 20Ă·2=10 students.

Question 13.

Which two instruments do an equal number of students play?

Answer:

From the above data, we can say that the equal number of students play woodwings and strings equally.

**Problem Solving**

Question 14.

Matthew measured the length of some bugs. He displayed the data in the line plot. Find 5 of Matthew’s errors.

Explain Matthew’s errors.

Answer:

According to the line plot,number of bugs of length \(\frac{2}{4}\) inches is 1.

Number of bugs of \(\frac{3}{4}\) inches length is 4.

Number of bugs of \(\frac{4}{4}\) inches length is 3.

Number of bugs of 1\(\frac{1}{4}\) inches length is 5.

Number of bugs of 1\(\frac{2}{4}\) inches length is 1.

From the above observations, Matthew’s errors are the number of bugs of length \(\frac{1}{4}\), \(\frac{3}{4}\) and \(\frac{4}{4}\) and also the two labels.

He needs to add one ‘x’ on \(\frac{1}{4}\)inch, \(\frac{3}{4}\) and \(\frac{4}{4}\).He also needs to change the lables of \(\frac{1}{4}\) inches and \(\frac{2}{4}\) to 1\(\frac{1}{4}\) inches and 1\(\frac{2}{4}\) inches respectively.

Question 15.

Refer to Exercise 14. If the bugs that are \(\frac{4}{4}\) inches in length were laid end to end, what would be their total length?

Answer:

Number of bugs of \(\frac{4}{4}\) inches length is 3.

If 3 bugs of length \(\frac{4}{4}\) inches or 1 inches were laid end to end, then the total length will be 1+1+1=3 inches

Question 16.

There are three elementary schools on Brown Street:

PS Elementary (PSE), PS Middle (PSM), and PS High (PSH).

- PSE is 1 mile from PSM.
- PSH and PSE are 2 miles apart.
- PSH is 3 miles from PSM.
- Use the facts above. What is the order of the schools on the street?

Answer:

From the above figure, we can say that the order of schools will be PSM, PSE and PSH.

**Test Practice**

Question 17.

According to the line plot, how many pets do most students have?

(A) 1 pet

(B) 2 pets

(C) 3 pets

(D) 4 pets

Answer:

Number of students having 0 pets are 5.

Number of students having 1 pets are 8.

Number of students having 2 pets are 6.

Number of students having 3 pets are 2.

Number of students having 4 pets are 1.

Most of the students have 1 pet, 8 students are having 1 pet.

**Reflect**

Use what you learned about data to complete the graphic organizer.

Now reflect on the ESSENTIAL QUESTION Write your answer below.

Answer:

1. Is it reasonable to say that the number of red marbles is twice that of yellow?

Answer:

Based on the data presented above, the number of red marbles equals 9, the number of yellow marbles equals 5, and twice the yellow colour equals 2Ă—5=10. As 9 is nearest number to 10, the statement that the number of red marbles is double that of yellow marbles is reasonable.