Solving a Mixture Problem Using Two Variables
A word problem involving mixing a solution that needs to be 25 percent chlorine is analyzed, the unknown identified, and a two-variable system of
Subject: unknown
Transcript: MAKE 12 GALLONS OF MILDEW STAIN REMOVER. THE UNKNOWNS ARE THE NUMBER OF GALLONS OF 5% LIQUID AND THE NUMBER OF GALLONS OF 85% LIQUID THE MANAGER WILL ADD
Some Problems are More Easily Solved Using Two Variables
A practical problem is presented that demonstrates a situation in which two variables and a system of equations is the easiest way to reach a solution.
Subject: unknown
Transcript: DIFFERENTLY-PRICED ITEMS, SMALL AND LARGE ROLLS. THOSE ARE OUR TWO UNKNOWNS. LET'S SOLVE THIS PROBLEM WITH TWO VARIABLES. WE'LL LET X STAND FOR THE PRICE OF
Solving a Rate-Time-Distance Problem Using One Variable
How to write an equation with one variable to solve a practical problem involving rate, time, and distance using a table to help organize the information.
Subject: unknown
Transcript: LEAVES. IT'S FLYING FASTER, SO IT CATCHES UP WITH THE FIRST PLANE. THE PLANES ARRIVE IN MILWAUKEE AT THE SAME UNKNOWN TIME. THIS IS A RATE TIME DISTANCE
Practical Problem: Wages of an Electrician and an Apprentice
Using the elimination method of calculate the hourly pay rates of an electrician and his apprentice on two different jobs given the total cost of each job.
Subject: unknown
Transcript: UNKNOWNS. WE WANT TO FIND OUT HOW MUCH IT COSTS PER HOUR TO HIRE AN ELECTRICIAN. THAT'LL BE X. WE ALSO WANT TO FIND THE HOURLY COST OF HIRING AN APPRENTICE
Practical Problem: Finding the Cost of a Taxi Ride
Writing an equation in slope-intercept form to solve a rate problem.
Subject: unknown
Transcript: RIDE IN THE FORM OF AN EQUATION? THERE ARE TWO UNKNOWNS, THE COST IN DOLLARS AND THE NUMBER OF MILES. SO WE'LL USE AN EQUATION WITH TWO VARIABLES, X AND
Solving a Complicated Cash Register Problem
A store manager needs to calculate how many bills of each denomination she can get with $100 in order to begin the day with enough change in her cash register, knowing she needs only one $20 bill. The solution is presented step-by-step.
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Two Solutions to a Complicated Copy Machine Problem
Complicated word problems are best handled by breaking them into simpler parts, as demonstrated in a rate and time problem. Two different approaches, both using a table to help organize the data, lead to the correct conclusion.
Subject: unknown
Transcript: UNKNOWN. THE QUESTION THE PROBLEM ASKS USUALLY POINTS TO THE UNKNOWN. IN THIS PROBLEM, THE UNKNOWN IS THE TIME IT TOOK BILL TO MAKE 780 COPIES. WE'LL LABEL
Two Solutions to a Complicated Bakery Problem
A complicated word problem involving a baker on a budget who wants to know how much white flour and how much rye flour he can purchase with his available funds. By reducing the problem to a series of simpler problems and employing a table to organiz...
Subject: unknown
Transcript: COLUMN? WE KNOW THAT THE BAKER NEEDS 100 POUNDS OF THE FLOUR MIX. WE DON'T KNOW THE AMOUNTS OF EITHER THE RYE OR THE WHITE, SO WE HAVE TWO UNKNOWNS. SHOULD
Some Problems are More Easily Solved Using One Variable
Although many problems can be solved with either one equation or a system of equations, one way will sometimes be easier than the other. A word problem involving finding the price per chair given the number of chairs, the total price, and the amount...
Subject: unknown
Transcript: ALSO SOLVE THIS PROBLEM WITH TWO VARIABLES. WE'D LET THE SECOND UNKNOWN BE THE TOTAL PRICE BEFORE TAX. WE'D WRITE TWO EQUATIONS. BUT ONE OF THE EQUATIONS