What number is 45% of 80 ??

3 tier seats tickets

Step-by-step explanation:

Let the friends that bought floor seats be x and let the friends that bought tier seats be y.

Thus;

x + y = 12 - - - (eq 1)

Floor seats tickets cost $15 each, and tier seats tickets cost $70 each. The total cost of the tickets was $345. Thus;

15x + 70y = 345 - - - (eq 2)

Let's make x the subject in eq (1)

x = 12 - y

Putting this for x in eq 2 gives;

15(12 - y) + 70y = 345

180 - 15y + 70y = 345

55y = 345 - 180

55y = 165

y = 165/55

y = 3

Put 3 for y in x = 12 - y to get;

x = 12 - 3

x = 9

Thus, they purchased 9 floor seats tickets and 3 tier seats tickets