Question

There are 450 seats in the lower level of a concert hall with b balcony seats in the upper level. So far, 170 tickets have been sold, which is 1/5 if the total number of seats in the concert hall. How many balcony seats are in the concert hall?

Answer 1

400 seats

Explanation:

1/5(450+b)=170

90+1/5b=170

90+1/5b-90÷170-90

1/5b=80

1/5b÷1/5÷80÷1/5

b=400 seats

Answer 2

There are 400 balcony seats in the concert hall.

Step-by-step explanation:

Step 1 :

• The number of lower seats = 450 seats

Total seats = Lower seats + balcony seats

Step 2 :

• Tickets sold = 170 tickets
• Total tickets = x

Tickets sold = 1/5 of total tickets.

⇒ 170 = (1/5)x

⇒ x = 5
`*`170

⇒ x = 850 tickets

∴ Total seats in the concert hall is 850.

Step 3 :

Total seats = 450 + balcony seats

850 - 450 = balcony seats

∴ balcony seats = 400