Answer:
About $3, 333.30
Step-by-step explanation:
If Karen makes $40,000 a year, that means she makes about $3,333.30 a month (12 months in a year, divide 40,000 by 12 to get the answer) this means she can budget about $3,333.30 a month.
(I rounded to make the answer more realistic the full number is 3333.3333333333333333333333333333)