The owner of a movie theater needs to bring in $1400 revenue at each screening in order to stay in business. She sells adults' tickets for $8 each and children's tickets at $3 each.

Step-by-step explanation:

Since we are not told what to look for, we can as well look for the number of adults and children tickets sold.

Let x be the number of adult's tickets sold

Let y be the number of children tickets sold.

Let the total amount of tickets sold be 400, then;

x+y = 400 1

If she sells adults' tickets for $8 each and children's tickets at $3 each and she needs to bring in a total revenue of $1400, then the equation can be modelled as:

8x+3y = 1400… 2

Solve equation 1 and 2 simultaneously.

Multiply equation 1 by 3 and 2 by 1:

3x+3y = 1200

8x+3y = 1400

Subtract

3x-8x = 1200-1400

-5x = -200

x = 200/5

x = 40

Substitute x= 40 into equation 1

x+y = 400

40+y = 400

y = 400-40

y = 360

This means that 40 adults tickets were sold and 360 children tickets were sold

Note that the total tickets was assumed.

the answer is 31.27mph

tip $2.90

total $17.40