A local diner has started selling cupcakes and is using the bar chart given below to keep track of how many are sold each day. How many cupcakes will be sold on day n?

a + (n-1)*4

Step-by-step explanation:

Day n could be any particular day located on the x-axis of the bar chart. Each bar represents the amount of cupcakes sold on each of the four days numbered from 1 to 4. The height of each bar marks the number of cupcakes sold. According to the chart attached, the number of cupcakes sold on each day is listed below:

Day 1 : 1 cupcake sold

Day 2 : 5 cupckaes sold

Day 3: 9 cupcakes sold

Day 4: 13 cupckaes sold

Studying the graph carefully fully, it will be observed that the number of cupcakes sold increases by a margin of 4 after day one.

As such the number of cupcakes sold in n days can be modeled by:

Using the Arithmetic progression formula:

Tn = a + (n-1)d

d = common difference, = 4

a = first term = 1

n = number of days

Hence, number sold in day n:

a + (n-1)*4

Arithmetic progressio