Of all the students in a school, 2/9
of them are in sixth grade.
a. How many sixth graders are there if the school has 90 students?
b. How many sixth graders are there if the school has 27 students?
c. If the school has x students, select the expression for the number of students in the school in terms of x.
d. How many students are in the school if 42 of them are sixth graders?