At a school’s cafeteria, 60 students ordered lunches. Every student ordered at least one lunch, and some took two. 55 took chicken lunches and 45 took fish lunches. How many took both lunches?

The students at jefferson middle school are raising money for a charity by selling t-shirts and hats. the number of t-shirts sold was 3 times the number of hats. the profit was $5 for each t-shirt sold and $2.50 for each hat sold. the students raised $840 for the charity. they used the system below to analyze their success and found the solution to be (144, 48). 5x+2.50y=840 x=3y how much did they earn from t-shirt sales?