Unit 1: Relationships Between Quantities UNIT 1 .

2y ago
34 Views
2 Downloads
750.45 KB
6 Pages
Last View : 22d ago
Last Download : 6m ago
Upload by : Abby Duckworth
Transcription

Unit 1: Relationships Between QuantitiesUNIT 1: RELATIONSHIPS BETWEEN QUANTITIESQuantities and UnitsMGSE9-12.N.Q.1 Use units of measure (linear, area, capacity, rates, and time) as a way to understand problems.MGSE9-12.N.Q.2 Define appropriate quantities for the purpose of descriptive modeling. Given a situation, context, or problem, students willdetermine, identify, and use appropriate quantities for representing the situation.MGSE9-12.N.Q.3 Choose a level of accuracy appropriate to limitations on measurement when reporting quantities. For example, money situationsare generally reported to the nearest cent (hundredth). Also, an answer’s precision is limited to the precision of the data given.KEY IDEAS1. A quantity is an exact amount or measurement. One type of quantity is a simple count, such as 5 eggs or 12 months. A second type ofquantity is a measurement, which is an amount of a specific unit. Examples are 6 feet and 3 pounds.2. A quantity can be exact or approximate. When an approximate quantity is used, it is important that we consider its level of accuracy. Whenworking with measurements, we need to determine what level of accuracy is necessary and practical. For example, a dosage of medicinewould need to be very precise. An example of a measurement that does not need to be very precise is the distance from your house to a localmall. The use of an appropriate unit for measurements is also important. For example, if you want to calculate the diameter of the Sun, youwould want to choose a very large unit as your measure of length, such as miles or kilometers. Conversion of units can requireapproximations.Example:Convert 309 yards to feet.Solution:3. The context of a problem tells us what types of units are involved. Dimensional analysis is a way to determine relationships among quantitiesusing their dimensions, units, or unit equivalencies. Dimensional analysis suggests which quantities should be used for computation in order toobtain the desired result.Example:The cost, in dollars, of a single-story home can be approximated using the formula C klw, where l is the approximate length of the home and wis the approximate width of the home. Find the units for the coefficient k.Solution:Example:Convert 45 miles per hour to feet per minute.Solution:

Unit 1: Relationships Between Quantities5. When data are displayed in a graph, the units and scale features are keys to interpreting the data. Breaks or an abbreviated scale in agraph should be noted as they can cause a misinterpretation of the dataExample:Meghan has 20 songs currently downloaded. Three times per week she downloads 4 additional songs. She wants to make a graph to display herdownloads for the next 3 months. Use the graph below to depict Meghan's download for the next 3 months. Make sure to label the axes.6. The measurements we use are often approximations. It is routinely necessary to determine reasonableapproximations.Example:When Justin goes to work, he drives at an average speed of 65 miles per hour. It takes about 1 hour and 30 minutes for Justin to arrive atwork. His car travels about 25 miles per gallon of gas. If gas costs 3.65 per gallon, how much money does Justin spend on gas to travel towork?Solution:REVIEW EXAMPLESm , where m is mass and v is volume. If mass is1. The formula for density d is d vmeasured in kilograms and volume is measured in cubic meters, what is the unit fordensity?Solution:2. A rectangle has a length of 2 meters and a width of 40 centimeters. What is the perimeter of the rectangle?40 cm2mPage 2

Unit 1: Relationships Between QuantitiesSAMPLE ITEMS1. A rectangle has a length of 12 meters and a width of 400 centimeters. What is the perimeter, in cm, of the rectangle?A. 824 cmB. 1,600 cmC. 2,000 cmD. 3,200 cm2. Jill swam 200 meters in 2 minutes 42 seconds. If each lap is 50 meters long, which is MOST LIKELY to be her lap time in seconds?A.B.C.D.32 seconds40 seconds48 seconds60 secondsStructure of ExpressionsMGSE9-12.A.SSE.1 Interpret expressions that represent a quantity in terms of its context.MGSE9-12.A.SSE.1a Interpret parts of an expression, such as terms, factors, and coefficients, in context.MGSE9-12.A.SSE.1b Given situations which utilize formulas or expressions with multiple terms and/or factors, interpret the meaning (incontext) of individual terms or factors.KEY IDEAS1. Arithmetic expressions contain numbers and operation signs.9 2Examples: 2 4, 4–(10 3 ), and5Algebraic expressions contain one or more variables.9 2tExamples: 2x 4, 4 x (10 3 y ), and5The parts of expressions that are separated by addition or subtraction signs are called terms.Terms are usually composed of numerical factors and variable factors. Factors are numbersmultiplied together to get another number. The numerical factor is called the coefficient.Consider the algebraic expression 4x 7y–3. It has three terms: 4x, 7y, and –3. For 4x, thecoefficient is 4 and the variable factor is x. For 7y, the coefficient is 7 and the variable is y. Thethird term, –3, has no variables and is called a constant.

Unit 1: Relationships Between Quantities2. To interpret a formula, it is important to know what each variable represents and tounderstand the relationships between the variables.Example: The formula used to estimate the number of calories burned while jogging, C 0.075mt,where m represents a person’s body weight in pounds and t is the number of minutes spent jogging. Thisformula tells us that the number of calories burned depends on a person’s body weight and how much timeis spent jogging. The coefficient, 0.075, is the factor used for jogging. Since sprinting burns more calories inless time, the coefficient for sprinting would be larger than 0.075.Important TipTo consider how a coefficient affects a term, try different coefficient values for the same term andexplore the effects.REVIEW EXAMPLES1. The number of calories burned during exercise depends on the activity. The formulas for two activities are given.C1 0.012mt and C2 0.032mta. If one activity is walking and the other is running, identify the formula that represents each activity.Explain your answer.b. What value would you expect the coefficient to have if the activity were reading?Include units andexplain your answer.SAMPLE ITEM1. The distance a car travels can be found using the formula d rt, where d is the distance, r is the rate of speed, and t is time. Billdrives his car at 70 miles per hour for 1/2 hour.Which term gives the distance Bill travels?A.1B.2C.(2)(70)D.(70)(1/2)Page 4

Unit 1: Relationships Between QuantitiesCreating Equations and InequalitiesMGSE9-12.A.CED.1 Create equations and inequalities in one variable and use them to solve problems. Include equations arisingfrom linear and exponential functions (integer inputs only).MGSE9-12.A.CED.4 Rearrange formulas to highlight a quantity of interest using the same reasoning as in solving equations.Examples: Rearrange Ohm’s law V IR to highlight resistance R.KEY IDEAS1. Problems in quantitative relationships generally call for us to determine how the quantities are related to each other, use avariable or variables to represent unknowns, and write and solve an equation. Some problems can be modeled using an equationwith one unknown.Example:The sum of the angle measures in a triangle is 180 . Two angles of a triangle measure 30 and 70 . What is the measure of the thirdangle?2. There are also problems that can be modeled with inequalities. These can be cases where you want to find the minimum ormaximum amount of something.Example:Sitong has at most 60 to spend on clothes. She wants to buy a pair of jeans for 22 and spend the rest on t-shirts. Each t-shirt costs 8. How many t-shirts can Sitong purchase?3. There are situations with two related variables that can be modeled with inequalities. These inequalities are called constraints.Example:Mark has 14 to buy lunch for himself and his sister. He wants to buy at least one sandwich and one drink. Sandwiches cost 5 anddrinks cost 2. Write three inequalities to represent the three constraints on the number of sandwiches and drinks Mark could buy.Can Mark buy 2 sandwiches and 2 drinks?5. In some cases a number is not required for a solution. Instead, we want to know how a certain variable relates to another.Example:Solve the equation m y 2 – y1x2 – x1for y 2 .

Unit 1: Relationships Between QuantitiesSAMPLE ITEMS1. The sum of the angle measures in a triangle is 180 . Two angles of a trianglemeasure 20 and 50 . What is the measure of the third angle?A.B.C.D.30 70 110 160 2. Which equation shows P 2l 2w when solved for w?2lP2l – PB. w 2PC. w 2l –2P – 2lD. w 2A. w 3. Bruce owns a business that produces widgets. He must bring in more in revenuethan he pays out in costs in order to turn a profit. It costs 10 in labor and materials to make each of his widgets. His rent each month for his factory is 4,000. He sells each widget for 25.What is the smallest number of widgets Bruce needs to sell each month tomake a profit?A.B.C.D.160260267400Page 6

Page 1 Unit 1: Relationships Between Quantities UNIT 1: RELATIONSHIPS BETWEEN QUANTITIES Quantities and Units MGSE9-12.N.Q.1 Use units of measure (linear, area, capacity, rates, and time) as a way to understand problems. MGSE9-12.N.Q.2 Define appropriate quantities for the purpose of descriptive modeling.

Related Documents:

Molar Thermodynamic Quantities or Partial Molar Quantities of Mixing 18 1.4.3 Relative Integral Molar Thermodynamic Quantities or Integral Molar Quantities of Mixing 19 1.4.4 Other Thermodynamic Functions and Relationships 21 . The enthalpy H can be described as

4 Physics data booklet. Adding/subtracting quantities: uncertainty in result will be sum of uncertainties of quantities. Multiplying/dividing quantities: % uncertainties of quantities are added together to obtain % uncertainty in result. Powers of quantities: % uncertainty of quantity is multiplied by power to obtain % uncertainty in result.

single real number, these quantities are often called scalars. Other quantities, such as directed distances, velocities and forces , require for their complete specification both a magnitude and direction, these quantities are called vectors. Vectors

5 Unit 1: Relationships between Quantities and Reasoning with Equations Overview At-a-Glance Unit #1 - Relationships between Quantities and Reasoning with Equations Unit Description: By the end of Algebra, students have learned to solve linear equations in one variable and have applied graphical and algebraic methods to analyze and solve systems of linear equations in two variables.

Trigonometry Unit 4 Unit 4 WB Unit 4 Unit 4 5 Free Particle Interactions: Weight and Friction Unit 5 Unit 5 ZA-Chapter 3 pp. 39-57 pp. 103-106 WB Unit 5 Unit 5 6 Constant Force Particle: Acceleration Unit 6 Unit 6 and ZA-Chapter 3 pp. 57-72 WB Unit 6 Parts C&B 6 Constant Force Particle: Acceleration Unit 6 Unit 6 and WB Unit 6 Unit 6

Unit 1: Relationships Among Quantities Key Ideas Unit Conversions Expressions, Equations, Inequalities Solving Linear Equations Solving Exponential Equations

other quantities measured in like or different units. For example, if a person walks 1/2 mile in each 1/4 hour, compute the unit rate as the complex fraction 1/2/1/4 miles per hour, equivalently 2 miles per hour. Recognize and represent proportional relationships between quantities.

The Baldrige Education Criteria for Performance Excellence is an oficial publication of NIST under the authority of the Malcolm Baldrige National Quality Improvement Act of 1987 (Public Law 100-107; codiied at 15 U.S.C. § 3711a). This publication is a work of the U.S. Government and is not subject to copyright protection in the United States under Section 105 of Title 17 of the United .