Unit 5 Test Review: Proportional Reasoning

Emma has a coupon for $5.25 off a frame that normally costs $15.00. What percent discount did she receive on the frame?

(a)  

Lincoln estimates the height of a tree. Lincoln's estimate has a 6% error.

The actual height of the tree is 17 feet. What could be Lincoln's estimate?

Choose all the correct answers.

• 11 feet

• 15.98 feet

• 18.02 feet

• 16.94 feet

The developer for a movie-streaming service wants to survey its customers to determine features for a new app. Which sampling method would produce a representative sample of the population of the movie-streaming service's customers? Decide if each sampling method is likely to produce a representative sample. Choose Yes or No for each method.

Groups:

(a) yes

,

(b) no

• Count the number of birds in the schoolyard and record the data. Survey the class and ask them to predict the number of birds the next day.
• Observe the growth of a seed in different types of soil and record the changes. Ask the class to predict the next stage of growth.
• Observe the behavior of a plant growing in different conditions and record the changes. Ask the class to predict the next stage of growth.

• Record the number of sunny days in a week. Survey the class and ask them to predict the number of sunny days in the next week.
• Record the temperature at different times of the day for a week. Survey the class and ask them to predict the temperature at a specific time the next day.

• Observe the behavior of ants in different environments and record the observations. Ask the class to predict the behavior of ants in a new environment.

• Observe the patterns of clouds in the sky for a week and record the observations. Ask the class to predict the cloud patterns for the next day.
• Observe the behavior of fish in a tank with different decorations and record the observations. Ask the class to predict the behavior of fish in a new tank.
• Ask the class to predict the outcome of a coin toss 10 times.
• Count the number of red cars passing by in 5 minutes and record the data. Survey the class and ask them to predict the number of red cars in the next 5 minutes.

• Spin a spinner four times and record the letters. Survey eve

• Measure the length of 10 different objects in the classroom and record the measurements. Ask the class to guess the length of an eleventh object.

• Roll a dice 10 times and record the numbers. Survey everyone in the class and ask them to predict the next number.

• Observe the behavior of a toy car on different surfaces and record the observations. Ask the class to predict the behavior of the car on a new surface.
• Measure the height of 10 different plants and record the measurements. Ask the class to guess the height of an eleventh plant.
• Observe the movement of the moon for a week and record the phases. Ask the class to predict the phase of the moon for the next day.

The box plots show the amount of rainfall, in inches, in two different towns during storms.

Express the difference in the median amount of rainfall as a multiple of the IQR for each data set.

• The difference in median amount of rainfall for Town A is 0.5 times the IQR and 0.4 times the IQR for Town B.

• The difference in median amount of rainfall is 2 times the IQR for each data set.
• The difference in median amount of rainfall for Town A is 0.4 times the IQR and 0.5 times the IQR for Town B.

• The correct answer cannot be determined without the specific data sets for the two towns.

Samuel buys 3 bottles of juice that each have an original price of 2.80. He uses a coupon for 35% off.

• 5.46
• 2.80
• 3.50
• 4.20

Grayson and Theo collect items to recycle. The table shows the number of metal and plastic items each person collects. If Grayson collects 400 items and Theo collects 300 items, who would be expected to have more metal items?

• Theo
• None of them collect metal items
• Grayson
• Both collect the same amount of metal items

The box plots show the number of broken crayons Tia finds in several packs of Brand A and Brand B crayons. The distance between the medians is 2 times the IQR for both brands. Suppose Tia opens 3 additional packs of Brand B crayons. Tia finds 0, 1, and 2 broken crayons. Does the distance between the medians become a greater or lesser multiple of Brand A's IQR? Explain your reasoning.

Liam and Sheila have a container with 400 letter tiles. Each letter tile shows either a consonant or a vowel. They each select a sample of letter tiles from the container, count the number that show vowels. and return the letter tiles to the container. They both collect 30 samples, as shown in the box plots. Shela's R Would it be better to use one of Liam's or Sheila's samples to make an estimate of the number of vowel tiles in the container? Explain your reasoning.

Last year, 470 people attended Fairfield Community Day. This year, 585 people attended the event. To the nearest percent, what is the percent change in the number of people who attended Fairfield Community Day?

• 50%
• 10%
• 24%
• 35%

Arielle wants to survey soccer players to determine whether they would prefer to wear short-sleeved or long-sleeved jerseys. Arielle decides to go to a soccer game and survey every fourth person in the bleachers.

Is this sample likely to be representative of soccer players? Explain your reasoning.