every year somerville has a citywide relay and reports the winning times. winning relay times according to…
every year somerville has a citywide relay and reports the winning times. winning relay times according to the graph, when was the rate of decrease greater? between 2014 and 2015 between 2016 and 2017
Answer
Explanation:
Step1: Calculate rate of decrease for 2014 - 2015
The winning - time in 2014 is 36 minutes and in 2015 is 20 minutes. The change in time $\Delta t_1=36 - 20=16$ minutes. The rate of decrease $r_1=\frac{36 - 20}{1}=16$ minutes per year.
Step2: Calculate rate of decrease for 2016 - 2017
The winning - time in 2016 is 32 minutes and in 2017 is 28 minutes. The change in time $\Delta t_2=32 - 28 = 4$ minutes. The rate of decrease $r_2=\frac{32 - 28}{1}=4$ minutes per year.
Step3: Compare the rates
Since $16>4$, the rate of decrease is greater between 2014 and 2015.
Answer:
between 2014 and 2015