Question

Help anyone? :D thank you <3
y varies jointly with p and q. When p = 7 and q = 2, y = 70. Find y when p = 8 and q = 4.

y = 120

y = 160

y = 200

y = 240

Answer 1

My friend taught me how to do these but i forgot :(

Answer 2

let y=kpq as y varies jointly with p and q
now When p = 7 and q = 2, y = 70
hence k=y/pq=70/(7*2)=5
hence y=5pq
p = 8 and q = 4.
or y=5*8*4=160
or y = 160

Answer 3

Thank you <3

Answer 4

welcome dear