MediumMath· Algebra· Linear equations in two variables· SPR
On a 210-mile trip, Cameron drove at an average speed of 60 miles per hour for the first x hours. He then completed the trip, driving at an average speed of 50 miles per hour for the remaining y hours. If , what is the value of y ?
Correct answer: 3
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Explanation
The correct answer is 3. It’s given that Cameron drove 60 miles per hour for x hours; therefore, the distance driven at this speed can be represented by . He then drove 50 miles per hour for y hours; therefore, the distance driven at this speed can be represented by . Since Cameron drove 210 total miles, the equation represents this situation. If , substitution yields , or . Subtracting 60 from both sides of this equation yields . Dividing both sides of this equation by 50 yields .
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id cb_question_bank:4ce05481-dea6-44c2-9f2c-47357f8fca04 · question 9c7741c6 · IBN 029899-DC
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