The guidelines at chens school state that there should be 2 adults chaperones for every 15 students on a field trip. Mrs. Rodriguez plans to take 90 students to a science museum. Beside Mrs. Rodriguez, there will be a 3 teachers attending the field trip. The other adults chaperones eill be parent volunteers. How many parent volunteers are needed?

According to the guidelines at Chen's school, there should be 2 adult chaperones for every 15 students on a field trip. Mrs. Rodriguez plans to take 90 students to a science museum, and there will be 3 teachers attending the field trip, including Mrs. Rodriguez.

To determine the number of parent volunteers needed, we can calculate the number of chaperones required for the students and subtract the number of teachers already attending.

Number of chaperones required for students:

90 students ÷ 15 students per chaperone = 6 chaperones

Number of chaperones needed in total (including teachers):

6 chaperones (for students) + 3 teachers = 9 chaperones

Since Mrs. Rodriguez is already one of the chaperones, we subtract her from the total:

9 chaperones - 1 (Mrs. Rodriguez) = 8 chaperones needed from parent volunteers

Therefore, 8 parent volunteers are needed to serve as chaperones for the field trip.