# Math

90% of students at a university use a backpack, while the rest do not. Of all the students, 50% carry their laptops with them and 5% carry neither a backpack nor laptop. What percentage of students carry their laptops and use a backpack?

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2. 👎 0
3. 👁 124
1. this would be VERY easy with a Venn diagram

looking at 100 students
... 90 use a backpack
... 50 carry a laptop
... 5 do neither

let b equal the number who do both

(90 - b) + (50 - b) + b = 100 - 5

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2. 👎 0

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