speed of second kid is X
they met after 20 minutes which means they walked in combine 3400m
that means
90*20+X*20=3400
20*X=1600
X=80 m/sec
sorry for english
speed of second kid is X
they met after 20 minutes which means they walked in combine 3400m
that means
90*20+X*20=3400
20*X=1600
X=80 m/sec
sorry for english