Problema Solution

if steve is writing a test and the rules of the test are if you get one wrong they take two marks away if you get one right you get one mark if he got 21 out of 30 how many did she get wrong

Answer provided by our tutors

let


x = the number of wrong answers

y = the number of right answers

30 = the total number of questions


y - 2x = 21


x + y = 30


by solving we find


x = 3


y = 27


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she got 3 wrong and 27 right.