You are given a math word problem and you are supposed to apply a single mathematical operator like addition, subtraction, multiplication, or division on the numbers embedded in the text to answer the following question and then only report the final numerical answer.

katie had 12 pencils in her desk and 3 more in her backpack . how many did she have total ?
15

it has been tradition in shiela 's home to hang a sock above the fireplace for each member of the family . this year she placed a cinnamon ball every day in the socks for 5 of her family members . how long can she do this if she bought 50 cinnamon balls ?
10

greg wants to buy a $ 90 scooter . he has saved $ 57 so far . how much more money does greg need ?
33