Question

Each time Samantha rides the train, she spends $4 for her fare. Write an integer that represents the change in her money from riding the train to and from work for 13 days. Explain your reasoning.

Answer 1

Integer -104 represents change in the money. Negative sign indicates money got reduced that is money with Samantha got reduced by $104 . 104 represents changes and –ve sign says it got spent( reduced).

Solution:

Given that amount spent by Samantha each time she ride on train = $4

That is fare of train for one side = $4

Let’s assume initial amount with Samantha =
`A_(i)` = $ x

Amount spent on train fare while going to work = $4

Amount spent on train fare while coming from work = $4

So total amount spent on one day = Amount spent while going to work + Amount spent while coming from work = $4 + $4 = $8

Amount spent by her in 13 days = amount spent in one day
`*` 13 = 8
`*` 13 =$104

So amount remaining with Samantha that is final amount =
`I_(f)` = x – 104

So change in amount = final amount – initial amount = (x – 104) – x = -104$

So Integer -104 represents change in the money. Negative sign indicates money got reduced that is money with Samantha got reduced by $104. 104 represent changes and –ve sign says it got spent (reduced).

Answer 2

Explanation:

Money spent for riding in the train in a day = 2 * $4 = $8

Money spent for riding in the train for 13 days = $8 * 13 = $ 104