Question

Alma borrows money from her mom to buy a $150 bike. She gives her mom $40 at the time of purchase and continues to pay her $10 each month until the bike is paid for in full. Alma wrote this equation to represent the amount y that she will have paid her mom after x months.Equation:y 5 40x 1 10Is her equation correct? How did she get that equation? If it is not correct, write a correct equation.

Answer 1

Given:

Total amount of bike = $150

Alma gives her mom $40 at the time of purchase and continues to pay her $10 each month until the bike is paid for in full.

Alma's equation:
`y=40x+10`

To find:

Whether her equation is correct or not.

Solution:

Let y be the amount that she will have paid her mom after x months.

She pays $10 each month.

She will $10x in x months.

Initially she gives $40 to her mom at the time of purchase. So, total amount she pays after x months is

Total amount
`=40+10x`

Since, y represents the amount that she will have paid her mom after x months, therefore

`y=40+10x`

Alma multiply the variable x with 40 instead of 10.

Hence, Alma is incorrect and the correct equation is
`y=40+10x`.