There is a non-mathematical fact that students must know about mixtures in order to answer this question. When salt is dissolved in water, the salt disperses evenly through the mixture, so any sample from the mixture that has the same volume will have the same amount of salt.

The purpose of this task is to show how the ideas in the RP and EE domains in 6th and 7th grade mature in 8th grade.

In this activity students become familiar with the math vocabulary more/less/same and most/least as they count and compare small groups.

This activity builds on Sort and Count I. It also helps students become familiar with the math vocabulary more/less/same and most/least as they sort, count, and compare small groups of objects.

The purpose of this task is to have students compute and interpret an expected value, and then use the information provided by the expected value to make a decision. The task is designed to encourage students to communicate their findings in a non-technical form in context.

The purpose of this task is to allow students to demonstrate an ability to construct boxplots and to use boxplots as the basis for comparing distributions. The solution should directly compare the center, spread, and shape of the two distributions and comment on the high outlier in the northbound data set.

The purpose of this task is to present students with a context that can naturally be represented with an inequality and to explore the relationship between the context and the mathematical representation of that context; thus, this is an intended as an instructional task.

This is a rectangle subdivision task; ideally instead of counting each square. students should break the letters into rectangles, multiply to find the areas, and add up the areas. However, students should not be discouraged from using individual counting to start if they are stuck. Often students will get tired of counting and devise the shortcut method themselves.

This task uses language, "half of the stamps," that students in Grade 5 will come to associate with multiplication by the fraction 12. In Grade 3, many students will understand half of 120 to mean the number obtained by dividing 120 by 2. For students who are unfamiliar with this language the task provides a preparation for the later understanding that a fraction of a quantity is that fraction times the quantity.

This problem can be solved in more than one way. The choice in solution method may reflect the comfort and mathematical sophistication of the student.

This is a multi-step problem since it requires more than two steps no matter how it is solved. The problem is not scaffolded for the student, but each step is straightforward and should follow from the previous with a careful reading of the problem.

In this task students design a plan to conduct a random sample of the students in their school to estimate the proportion of students who think their parents are strict.

This task provides a familiar context allowing students to visualize multiplication of a fraction by a whole number. This task could form part of a very rich activity which includes studying soda can labels.

In this task students must figure out how much fresh water you must add to get a particular salt concentration in aquarium water.

This problem provides students with an opportunity to discover algebraic structure in a geometric context. More specifically, the student will need to divide up the given polygons into triangles and then use the fact that the sum of the angles in each triangle is 180_.

Parts (d) and (e) of this task constitute a very advanced application of the skill of making use of structure: in (d) students are being asked to use the defining property of even and odd functions to manipulate expressions involving function notation. In (e) they are asked to see the structure in the system of two equations involving functions.

The intent of this problem is to have students think about how function addition works on a fundamental level, so formulas have been omitted on purpose.

This is a task from the Illustrative Mathematics website that is one part of a complete illustration of the standard to which it is aligned. Each task has at least one solution and some commentary that addresses important aspects of the task and its potential use.