Nicholas spent 13 dollars on a magazine and some erasers. if the magazine cost 4 dollars and each eraser cost 3dollars then how many erasers did he buy?

Nicholas bought 3 erasers.
To do this, you first subtract $4 from $13 to get how much money he has left to buy the erasers.

$13-$4=9

After this, you divide $9 by $3 to find how many erasers he bought. $9 is how much money he has left while $3 is the cost of each eraser.

$9 / $3 = 3

Therefore, Nicholas bought 3 erasers.

I hope this helped you!