STAAR Review Interpret Data

A survey of visitors at a national park was conducted to determine the preferred activity of each visitor to the park. Each visitor chose one activity. The survey results are shown in the table.

Based on this information, which prediction about the preferred activity for the next 200 visitors to the park is the most reasonable?

• The number of visitors who prefer water sports will be 5 more than the number of visitors who prefer biking trails.

• The number of visitors who prefer hiking trails will be 8 more than the number of visitors who prefer water sports.

• The number of visitors who prefer camping will be 15 times the number of visitors who prefer hiking trails.

• The number of visitors who prefer camping will be 2 times the number of visitors who prefer water sports.

Answer explanation

To determine the most reasonable prediction about the preferred activity for the next 200 visitors to the park, the student could have found the number of visitors out of 200 who probably prefer each type of activity. Since the survey is of 80 visitors and 28 of those visitors prefer camping, the proportion (comparison of two ratios) to find the predicted number of visitors who prefer camping, w, out of 200 is 28 w = 80 200. To find the value of w, the student could have multiplied 28 by 200, resulting in 5,600, and then divided 5,600 by 80, resulting in w = 70 visitors who prefer camping. Similarly, proportions to find the predicted number of visitors who prefer hiking trails, x; the number of visitors who prefer water sports, y; and the number of visitors who prefer biking trails, z, are , 22 x = 80 200 14 y = 80 200, and 16 z = 80 200. Solving these proportions results in predicted numbers of 55 who prefer hiking trails, 35 who prefer water sports, and 40 who prefer biking trails. Therefore, the number of visitors who prefer camping will be 2 times the number of visitors who prefer water sports since 35 × 2 = 70. The rationale for the correct answer is an efficient way to solve the problem. However, other methods could be used to solve the problem correctly.

Tags

CCSS.7.SP.A.2

The dot plots show the numbers of apples picked by members of two different tour groups at an orchard.

Which statement correctly compares these two data sets?

• The median of the data is the same for both data sets.

• The mode of the data is the same for both data sets

• The range of the data is the same for both data sets.

• The distribution of the data is symmetrical for both data sets.

Answer explanation

To determine which statement is supported by the information in the dot plots (graphs that use dots to display data), the student should have calculated the stated measures of center and spread for each plot. The range (difference between the greatest and least values in a set of data) for Tour Group 1 is 10 − 1 = 9, and the range for Tour Group 2 is 10 − 1 = 9. Therefore, the range of the data is the same for both data sets.

Tags

CCSS.HSS.ID.A.3

The table shows the numbers of different types of pies sold at a bakery during one day.

Based on the results in the table, which statement about the pies sold at this bakery during one week is NOT true?

• It is two times as likely for a chocolate pie to be sold as for a lemon pie to be sold.

• It is equally likely for an apple or pecan pie to be sold as for a chocolate pie to be sold.

• It is more likely for an apple or lemon pie to be sold than for a pecan or chocolate pie to be sold.

• It is less likely for a pecan pie to be sold than for a lemon pie to be sold.

Answer explanation

To determine which statement is NOT true based on the results in the table, the student could have used the data given in the table for pies sold during one day and could have used the assumption that the number of pies sold during one week would be seven times the number of pies sold during one day. The student could have determined that 35 apple pies, 21 pecan pies, 28 lemon pies, and 56 chocolate pies sold during one week. The student could have identified that the statement indicating that it is more likely for an apple or lemon pie (35 + 28 = 63) to be sold than for a pecan or chocolate pie (21 + 56 = 77) to be sold is NOT true based on the results in the table. The rationale for the correct answer is an efficient way to solve the problem. However, other methods could be used to solve the problem correctly.

Tags

CCSS.7.SP.C.6

The box plots show the numbers of lessons completed by individual students enrolled in an online program at two different schools.

Which statement is best supported by the data in the box plots?

• The range of the data for School 1 is greater than the range of the data for School 2.

• The median of the data for School 2 is greater than the median of the data for School 1.

• The interquartile range of the data for School 2 is greater than the interquartile range of the data for School 1.

• The students at School 1 completed more lessons than the students at School 2.

Answer explanation

To determine which statement is supported by the information in the box plots (data displays that show the minimum, first quartile, median, third quartile, and maximum of sets of data), the student should have determined the median (middle number in a set of numbers when the set is ordered by value) for both box plots. The median of the data for School 1 is 5, and the median for the data for School 2 is 7. Therefore, the median of the data for School 2 (7) is greater than the median of the data for School 1 (5).

Tags

CCSS.7.SP.B.4