Answer:
7
Explanation:
We know that the first store charges $12.50 per month, which is a initial condition, and charges additionally $1.50 per movie, which is variable, this represents the ratio of change, so this can be expressed as
![\$12.50 + \$1.50x](https://img.qammunity.org/2020/formulas/mathematics/middle-school/26vfamcem3cseq83cs9thvvtpbk3epxkcx.png)
Where
represents movies.
Now, the second store doesn't charge and membership fee, just it charges a cost per movie which is $3.50.
Then, to solve the minimum number of movies needed to Plan A be the best choice, we just have to solve the following inequality
![\$12.50 + \$1.50x> \$3.50](https://img.qammunity.org/2020/formulas/mathematics/middle-school/op8z1i6sap4t7z3p3jbazhbknicm3op21i.png)
Which expresses the case where Plan A is a better choice, solving for
, we have
![\$12.50 + \$1.50x> \$3.50x\\\$1.50x - \$3.50x >-\$12.50\\(-1)(-2x)>(-12.50)(-1)\\2x<12.50\\x<(12.50)/(2)\\ x<6.25](https://img.qammunity.org/2020/formulas/mathematics/middle-school/e89bxusdbcnsdo1el0x9jlwy9xy5ho43or.png)
Which means that the minimum number of movies is 7, which is the next whole number after 6.