Choose No Solution, One Solution, or Infinitely Many Solutions for each equation 8p+1=4p+2

What is the size of the matrix resulting from

In the sixth grade 13 out of 20 students have a dog if there are 152 sixth grade students how many of them have a dog

60 musicians applied for a job at a music school. 14 of the musicians play both guitar and drums. what is the probability that the applicant who gets the job plays drums or guitar?