Plot the given points and use them to identify the trend.
The 9th month.
Practice makes perfect
We are given the daily customer average of a coffee shop for several consecutive months.
Month
Daily Customer Average
1
225
2
298
3
371
4
444
The coffee shop owner wants to open a second shop when his daily customer average reaches 800 people. We want to know during what month can he open a second shop if the trend of the daily customer average continues. To do so, let's start by plotting the given points in a coordinate system to look for a trend.
The trend seems to be linear. The daily customer average seems to increase by the same amount every month. We will check this observation by calculating the difference in the daily customer averages in consecutive months.
Months
Difference in Daily Customer Average
1 and 2
298-225=73
2 and 3
371-298=73
3 and 4
444-371=73
The difference is indeed the same. Assuming the same increase in the future, we can find the predicted customer number by adding 73 to the customer number of the previous month.
Month
Predicted Daily Customer Average
5
444+73=517
6
517+73=590
7
590+73=663
8
663+73=736
9
736+73=809
We can see that the daily customer average will first increase above 800 in the ninth month.
Assuming that this trend continues, the shop owner can open a second coffee shop in the ninth month.
