Hi there! I really need help with these two questions.
1) How many squares in a 2x3 plane have two or more vertices on dots in a grid? All dots are an equal distance from their nearest neighbors.
2) A test had 12 problems, and each problem is with five marks. Full marks are given for a correct answer, two marks given if there is no answer, and no marks are given for an incorrect answer. Some scores between 1 and 60 or impossible to get on this test. What is the sum of these impossible to get scores?
Thank you!
If there are x correct answers and y unanswered, then the score is 5x+2y
So just list all the combinations where x+y=12 to get all the possible scores.