Question

The graph shows the amount of savings over time in Eliana​'s account. Lana​, ​meanwhile, puts ​$50 each week into her savings account. If they both begin with​ $0, who is saving at the greater​ rate?

Select the correct choice below and fill in the answer boxes to complete your choice.
A.
Lana saves at a greater rate because her unit rate of ​$_ per week is greater than Eliana​'s unit rate of ​$_ per week.
B.
Eliana saves at a greater rate because her unit rate of ​$_ per week is greater than Lana​'s unit rate of ​$_ per week.

Answer 1

A. Lana saves at a greater rate because her unit rate of $50 per week is greater than Eliana's unit rate of $48 per week.

Explanation:

Eliana​'s savings per week = the rate of change of the graph

The rate of change of the graph given =
`(y_2 - y_1)/(x_2 -x_1)`

Using the points (0, 0) and (2, 96),

Rate of change =
`(96 - 0)/(2 - 0) = (96)/(2) = 48`

This rate of change means, Eliana puts $48 dollars per week into her account.

Since Lana's saving rate per week is $50, therefore:

Lana saves at a greater rate because her unit rate of ​$50 per week is greater than Eliana​'s unit rate of ​$48 per week.