Surveying was done for 275 students in the engineering Faculty. We found that 90 study Spanish, 96 study Chemistry, 167 study Mathematics, 18 studies Spanish and Chemistry, 75 study Chemistry and Math, 20 study Math and Spanish, and 15 studies all three subjects. By using the Venn diagram find the probability that a student selected at random studies: 1-Find the number of students take Math and Chemistry but not Spanish. 2- Find the probability that the student takes just chemistry. 3- Find the probability that the student takes just one of these subjects. 4- Find the probability that he takes Spanish, given that he studies Math