SAT Math: Choosing a System of Equations to Represent a Truck's Load

A truck is shipping bars of iron and bars of copper. One copper bar weighs 50 pounds, and one iron bar weighs 40 pounds. The entire shipment weights 2670 pounds, and there are a total of 60 bars of metal. Which of the following systems of equations accurately represents c, the number of copper bars, and i, the number of iron bars?

Heart of AlgebraSystems of linear equations in two variables (word problems)
Product TypeSAT Math
SATSAT Math
SAT MathAlgebra and Functions
Heart of Algebra
Test PrepSAT Math

Transcript

00:15

seventy pounds and are a total of six hours of

00:17

metal Filing systems of equations accurately represents See the number

00:19

of copper bars and i the number of iron bars

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Okay when you answer these always look first at the

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answer sets Sometimes they'll throw in a d or a

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letter e or a w in there And you could

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just cross that off and get a freebie and improve

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your odds of getting the right answer But here they

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give you no such favors So let's prove our math

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medal medal there Alright by diving right into this problem

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it says that c is the number of copper bars

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and that i is the number of iron bars Well

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it also says there are a total of sixty bars

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of metal either one So we can add up both

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types to arrive at the first equation Right So c

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plus size sixty weigh in one more factor The wait

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wait though the way copper bars weigh fifty pounds each

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so give See a coefficient of fifty iron bars weigh

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forty pounds each so i get to go efficient They're

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a forty right forty i The total weight is two

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thousand six hundred seventy that's total so that's what everything

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that should equal right fifty c plus forty eyes to

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six Seven Oh put these two equations together to get

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the system of equations that we need that c plus

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size sixty and fifty c plus forty i is twenty

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six seventy and that's it the answer's Right there You

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can sort of feel good about yourself go home and

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don't know unwrap a nice metal bar and not eat 00:01:33.315 --> [endTime] it You know lower calories in chocolate bars though