Alicia bought n notebooks that cost $3 each. She paid for the notebooks with a $20 bill. Assuming there is no sales tax, what expression shows the amount of change Alicia should receive?
multiple choice are
a) 3n - 20
b) 20 - 3 - n
c)3n + 20
d) 20 - 3n
multiple choice are
a) 3n - 20
b) 20 - 3 - n
c)3n + 20
d) 20 - 3n
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20 dollars is a constant so it should be the amount started with and therefore should be positive
3 dollars each book is the cost per book
n is the number of books
3n is the amount paid for the books in total
if you want change you subtract what you pay for the items from the amount you paid
change = 20 - cost of books... = 20 - 3n
does that helpl
3 dollars each book is the cost per book
n is the number of books
3n is the amount paid for the books in total
if you want change you subtract what you pay for the items from the amount you paid
change = 20 - cost of books... = 20 - 3n
does that helpl
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If she paid $3 per book 2 would cost her 2*$3, 3 would cost her 3*$3 and n would cost her n*$3
If she pays with a $20 bill she will pay n*$3 < or = $20
n< or = 20/3 and n must be integer so
n = 6
cost 6*$3 = $18 so $2 change
If she pays with a $20 bill she will pay n*$3 < or = $20
n< or = 20/3 and n must be integer so
n = 6
cost 6*$3 = $18 so $2 change