# Math test

Obelix filled a mathematical test in which he answered 25 questions. For every correct answer, he received 5 points, for each bad answer he had 3 points deducted. Obelix gained 36% of all points in the test. How many questions did he solve correctly?

Correct result:

n =  15

#### Solution:

5n - 3(25-n) = 0.36 • 25•5

5•n - 3•(25-n) = 0.36 • 25•5

8n = 120

n = 15

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