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Current time:0:00Total duration:2:55

Linear equation word problems — Basic example

Video transcript

Kaleigh wants to do well in her classes so she is budgeting her time carefully to decide the number of classes see she will take this year for each class that she takes she expects to spend she expects us to spend two and a half hours each week working on homework she expects to spend an additional six and a half hours each week completing the assigned reading for all of her classes together if Kaley has 19 hours available each week to complete homework and reading for her classes which equation best models of the situation all right so she has a total of 19 hours available she has 19 hours available and she needs to she has a 19 hours available each week to complete homework 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 expect to spend two and a half hours each week working on homework four well actually I should say over here for each class that she takes she expects to spend two and a half hours each week working on homework let me underline that for each class that she takes she expects to spend two and a half hours each week working on homework so it's going to be two and a half to two and a half hours each week per class now how many classes is she taking well she's gonna take C classes 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 two and a half times C up in parenthesis just to make it clear what I'm doing here so it's gonna be two and a half times C is he mad she spends on homework and how much is she gonna spend on reading well it says over says over here she expects to spend an additional six and a half hours each week each week completing the assigned reading for all of her classes together so this Center says it doesn't matter how many classes she takes she's gonna spend six and a half hours reading so she's it's not a 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 nine 18 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 let's see they have 2 and a 2 and 1/2 C minus 6 and 1/2 no that's not this right over here 2 and 1/2 C plus 6 and 1/2 yep that's what we have over here is equal to 19 yep that's this choice the only difference between this and what I wrote is they just swapped the the two sides of the equality which you can always do these other choices let's see 6 and 1/2 times C well this would imply that you're spending 6 and 1/2 hours per class so that's not right and then this is also 6 and 1/2 times C so that's not going to work out either