Brad is an organizer of the Bolder Boulder 10K race and must hire workers for one day to prepare the race packets. Skilled workers cost $60 a day, and students cost $40 a

day. Brad can spend no more than $1,440. He needs at least 1 skilled worker for every

3 students, but only 16 skilled workers are available. Skilled workers can prepare 25

packets per hour, and students can prepare 18 packets per hour. Find the number of

each type of worker that Brad should hire to maximize the number of packets produced.