F(x) is the percent incorrect on a test when there are 25 questions correct and X questions incorrect. What is the function? How many questions were incorrect if the percentage of incorrect questions in 25%?
f(x)= x/x+25( it has to be divided by the total number so it would x +25 and you want incorrect so x would the numerator, good way to check is if you have 50 questions how do you get 50%?) .25= x/x+25 .25x + 6.25= x .75x= 6.25 x= 8.3333 so around 8 or 9 questions
f(x) /100 = x/(25 + x) then cross multiply f(x) ? (25 + x) = 100x so f(x) = 100x / (25 + x) then 25 =100x / (25 + x) 25(25 + x) = 100x 625 +2 5x = 100x 625 = 75x so x = 625