Answer:
40
Step-by-step explanation:
(120 - 40)/2 = 80/2 = 40
As 1/3 = 2/6 = 3/9 = 4/12
and 2/6 is greater than 1/6
3/9 is greater than 2/9
etc..
So
1/3 is greater than 1/6 ; 2/9 ; ...
16 days since 2/5 is 0.4 and there was 40 days then 2/5 * 40 is 16
Since we already know that there is a 25% chance to guess the correct answer to a multiple choice question, all we have to do is multiply .25 and 68 to get the expected amount of answers a student can possibly guess. We multiply .25 since it is the decimal form of 25% and 68 is our total questions.
.25 x 68 = 17
Therefore, a student can expect to guess 17 answers correct on a test with 68 multiple choice questions.