Question
An online bookstore sells novels and magazines. Each novel sells for $4, and each magazine sells for $1. If Sadie purchased a total of 11 novels and magazines that have a combined selling price of $20, how many novels did she purchase?
- 2
- 3
- 4
- 5
Hint:
Hint:
The elimination method is the process of eliminating one of the variables in the system of linear equations using the addition or subtraction methods in conjunction with multiplication or division of coefficients of the variables.
The correct answer is: 3
Let x be the number of novels and y be the number of magazines that
Sadie purchased.
If Sadie purchased a total of 11 novels and magazines,
Then x + y = 11.
It is given that the combined price of 11 novels and magazines is $20. Since each novel sells for $4 and each magazine sells for $1, it follows that
4x + y = 20. So the system of equations below must hold.
4x + y = 20
x + y = 11
We will solve these equations by elimination method
Subtract second equation from the first equation we get ,
4x + y – (x + y) = 20 - 11
4x + y – x - y = 9
3x = 9,
So x = 3.
Therefore, Sadie purchased 3 novels.
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