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SAT (Fall 2023)
Course: SAT (Fall 2023) > Unit 10
Lesson 1: Heart of algebra- Solving linear equations and linear inequalities — Basic example
- Solving linear equations and linear inequalities — Harder example
- Interpreting linear functions — Basic example
- Interpreting linear functions — Harder example
- Linear equation word problems — Basic example
- Linear equation word problems — Harder example
- Linear inequality word problems — Basic example
- Linear inequality word problems — Harder example
- Graphing linear equations — Basic example
- Graphing linear equations — Harder example
- Linear function word problems — Basic example
- Linear function word problems — Harder example
- Systems of linear inequalities word problems — Basic example
- Systems of linear inequalities word problems — Harder example
- Solving systems of linear equations — Basic example
- Solving systems of linear equations — Harder example
- Systems of linear equations word problems — Basic example
- Systems of linear equations word problems — Harder example
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Linear equation word problems — Basic example
Watch Sal work through a basic Linear equations word problem.
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At 2.45, I understood the answer but confused the difference between answer 2 and 4 why 4 is not correct answer as it is also the addition(6 votes)
Let's break the problem down to clear up any confusion. The variable we will use to represent the number of classes Kaylee will take is c.
- Kaylee has 19 hours available each week to complete homework. With this information, we can start the equation: ... = 19
- Kaylee is planning on spending 2 1/2 hours doing homework for each class that she takes. This means that we have to multiply the number of classes that she will take: c by 2 1/2 to find the total number of hours she will spend doing homework total. The equation that we have now is: 2 1/2c + ... = 19
- Finally, we are told that Kaylee will spend an additional 6 1/2 hours total doing assigned readings, not 6 1/2 hours for each class. The final equation will be: 2 1/2c + 6 1/2 = 19.
Does that make sense? Option #4 is incorrect because it shows that Kaylee will do 6 1/2 hours of reading for each class, which is not the case. I hope this helped! :)(71 votes)
Anybody else getting extreme stress about having to take the SAT in the far future?(33 votes)
yep, im so scared even though im taking the spring dsat which is still 6 months away(12 votes)
I did not understand why we are not multiplying c with 6 1/2(2 votes)- This is because Kaylee will spend an additional 6 1/2 hours working on reading for all of her classes altogether, not for every individual class. Hopefully that clears up any confusion :)(27 votes)
- What easy way can I remember these problems?(6 votes)
- Try breaking it down piece by piece. to have an easy knowledge of the problem(7 votes)
- what's the best way to get better at word problems like this?(2 votes)
- understaning the meaning of each symbol or placment of the numbers , so in theory , actually UNDERSTANDING why things are placed in the way that they are will help later understand it in different contexts. For example y=mx+b ;the Y represents a total , m represent a slope and b is the y- int , when you understand the meaning of these values it's easier to understand it in different contexts ( word problems ) .(13 votes)
Over all, this was a fairly easy problem.(8 votes)- How many questions will there be on the digital version of the SAT?(4 votes)
98 questions total (54 reading and writing + 44 math)(7 votes)
- thats indeed a great way of calculating your time. I aprove it !(6 votes)
At0:00, Praise the sun!(4 votes)
0:00Video transcript
- [Instructor] Kaylee wants
to do well in her classes, so she is budgeting her time
carefully to decide the number of classes, C, she will take this year. For each each class that she
takes, she expects to spend 2 1/2 hours each week working on homework. She expects to spend an
additional 6 1/2 hours each week completing the assigned reading for all of her classes together. If Kaylee has 19 hours available each week to complete homework and
reading for her classes, which equation best models the situation? Alright, so she has a total
of 19 hours available. She has 19 hours available. She has 19 hours available
each week to complete homework and reading for her classes. So how much time is it going to take her to complete the homework? Well it says that she
expects to spend 2 1/2 hours each week working on homework for, well actually I should say over here, for each class that she
takes, she expects to spend 2 1/2 hours each week working on homework. Let me underline that. For each class that she
takes, she expects to spend 2 1/2 hours each week working on homework. So that's going to be 2 1/2 hours each week per class. Now how many classes is she taking? Well she's gonna take C classes. So the total amount that
she spends on homework, so the amount that she spends
on homework is going to be 2 1/2 times C, up in parentheses just to make
it clear what I'm doing here. So it's gonna be 2 1/2
time C is the amount of time she spends on homework. And how much is she going
to spend on reading? Well, it says over here she expects to spend an
additional 6 1/2 hours each week completing the assigned reading for all of her classes together. So this sentence says it doesn't matter how many classes she takes, she's gonna spend 6 1/2 hours reading. So, it's not dependent on the
number of classes she takes. So this is the amount of time she's just gonna spend reading. And so the amount she spends on homework plus the amount she spends on reading need to add up to 19 hours. So which of these choices are
what I just wrote over here? So let's see, they have
the 19 on the other side but you see they have 2 1/2 C minus 6 1/2, no that's not this right over here. 2 1/2 C plus 6 1/2, yup
that's what we have over here, is equal to 19, yup that's this choice. The only difference between
this and what I wrote is they just swapped the
two sides of the equality which you can always do. These other choices, let's see 6 1/2 times C, well this would
imply that you're spending 6 1/2 hours per class so that's not right. And then this is also 6 1/2 times C, so that's not gonna work out either.