Question

Samantha just opened a new restaurant. She earned $550 on the first day and $750 on the third day that she was open for business. If Samantha's earnings continue to increase at the same rate, by how much are her earnings increasing each day? $________ per day Show your work. HINT: Find the slope.

Answer 1

Explanation:

If Samantha's earnings continue to increase at the same rate, this means that her earning is increasing arithmetically.

If she earned $550 in the first day, we can say the first term is $550

If she earned $750 on the third day, we can say the third term is $750

For us to know by how much her money is increasing, we need to find the common difference d formed by the sequence

550, x , 750

T1 = 550

T2 = x

T3 = 750

Common difference d = T2-T1 = T3-T2

x - 550 = 750 - x = d

Let's calculate the second term first i.e x

Since x - 550 = 750 - x = d

x - 550 = 750 - x

Collect like terms

x+x = 750+550

2x = 1300

x = 1300/2

x = 650

d = T2-T1

d = x - T1

d = 650-550

d = 100

Hence her money keeps increasing by $100 each day