Question

few persons booked a room in a hotel for rs 1200. three of members failed to reach, so the other had to pay rs 20 more each. find no. of persons​

Answer 1

Answer:

Step-by-step explanation:

total cost = 120 rs

let,

    total people = x

   cost for each person=y

   xy =total cost

   xy =120 rs----------- (Eqn 1)

if 3 members failed to come,

 total people = x-3

 cost for each person = y +20

 total cost : (x-3)(y+20) = 120 rs------------(Eqn 2)

equating eqn.1 and eqn.2

(x-3)(y+20) = xy

xy+20x-3y-60=xy

20x-3y-60=0

20x=3y+60

x=(3y+60)/20---------------(Eqn. 3)

substituting Eqn. 3 in Eqn. 1

xy= 1200

(3y+60)y/20=120

3y^2+60y=2400

3y^2+60y-2400=0

y^2+20y-800=0

(y+40)(y-20)=0

y=20 since money cant be negative

no of people = 120/20=6