Question

Lucia gave Brenda half of the cash she had in the store counter at the end of the day. Brenda put the money in her purse and added one half of the amount she had from her own savings. Brenda had saved half of what Lucia earned in the store that day. Brenda took her purse and went to the dog shelter and brought food and treat packet for 5 dogs. Each packet cost her $15. How much money did Lucia earn at the store that day?

Answer 1

$100

Explanation:

The amount Lucia gave Brenda = Half the amount in the store counter

The amount Brenda added to the money Lucia gave her = Half the amount in her (Brenda) savings

The amount Brenda had saved = Half of the amount Lucia earned in the store that day

The number of food and treat packets Brenda bought = 5

The cost of each packet = $15

Let x represent the amount Lucia earned and let y represent the amount Brenda saved

We have;

x/2 = y

x/2 + y/2 = 15 × 5 = 75

Therefore, we get;

y + y/2 = 75

(3/2)·y = 75

y = 75 × 2/3 = 50

y = 50

From x/2 = y, we have;

x/2 = 50

x = 2 × 50 = 100

The amount Lucia earned in her store that day, x = $100