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Maria spend 5 hours studying and earned a 90 on her exam. If you want to score a 81, how much time do you need to spend studying?

1 Answer

7 votes

Answer:

4hrs 30 mins

Explanation:

5hrs-90

x-81

cross multiplying gives us

405-90x then dividing through made x=4.5 which is = 4hrs 30mins

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