Answer:
Andrea can only buy one snack.
Explanation:
okay so since she had 18 dollars at first write it down. so,you would simply put $18 vertically (up) and then Andrea spent 6.50 on a notebook. write that down as well. so now under the "$18" write -6.50. that equals $11.5. but, Andrea needs to save 5.75. so, subtract that from the 11.5 that you wrote under 6.50. (a little check up right here/clarification) write $18-$6.50=$11.5 DO THIS VERTICALLY (UP) ! okay so now that you have that $11.5 written down, subtract 5.75 (for Andreas savings) $11.5-5.75= 5.75.
so you're work should look like this
$18.
$-6.50
-----------
$11.5
$-5.75
-------------
$5.75
just make sure you add the top ones like you know, the carry the one and stuff, just so she doesn't assume you copied of the internet . have a good day! i wish you the best of luck on this assignment !