Question

Kristen found that in 8th grade she studies 2.2 hours a week more than she did in 7th grade. If this trend continues until her senior year of high school, how many more hours will she study per week in 12th grade than she did in 7th grade?

a) 8.8 hours
b) 11 hours
c) 13.2 hours
d) 15.4 hours

Answer 1

Kristen will study 11 hours per week more in 12th grade than she did in 7th grade by multiplying the yearly increase of 2.2 hours by the 5 years from 8th to 12th grade.

Step-by-step explanation:

To calculate how many more hours Kristen will study per week in 12th grade than she did in 7th grade, we note that she studies 2.2 hours more each subsequent year. We count the number of years from 8th grade to 12th grade: 8th, 9th, 10th, 11th, and 12th. This represents 5 grade levels beyond 7th. To find the total additional hours studied by 12th grade, we multiply 2.2 hours by 5 years (2.2 hours/year * 5 years).

2.2 hours/year * 5 years = 11 hours/week

Therefore, Kristen will study 11 hours per week more in the 12th grade than she did in 7th grade, which corresponds to option b).