Please help with the Writing and Science answer. I've tried 336 on writing and 16.50, both are incorrect.

Susan Shi owns TestTutor, an educational tutoring center in Greenville, South Carolina. The center offers private tutoring in math, writing, and science. Information about the tutoring sessions is as follows: Writing $50 30 Session price Variable labor costs Variable supplies cost Session length Number of sessions demanded per week Math $34 20 2 45 minutes 180 Science $25 10 1 30 minutes 120 2 90 minutes 260 Since the company opened five years ago, demand has grown faster than the supply of qualified tutors. Susan currently has enough tutors to provide only 420 hours of tutoring each week. Susan has decided that instead of offering individualized instruction in math and science, she will switch to group sessions. Each math session will accommodate two students, and each science session will accommodate four students. Each student in the group will continue to pay the original session price. All sessions will have a single tutor, but each student will need supplies. Calculate the total hours needed with the group sessions. (Round answers to 2 decimal place, e.g. 15.25.) Hours needed 67.50 Math 390 Writing 15 Science 472.50 Total How will this change in service delivery affect Susan's ability to meet demand? How will it change her allocation of tutor hours? (Round answers to 2 decimal places, e.g. 15.25.) Susan will not have enough capacity to cover all sessions. Hours used Math 67.5 Writing 336.25 16.25 Science