Answer:
b= 10 miles/hr and c= 5 miles/hr
Step-by-step explanation:
Let it's downstream and upstream speed be d and u respectively
also speed of the boat be b and speed of stream be c.
as per question d = 150/10= 15 miles/hr
and, u= 150/30= 5 miles/hr
also we know d= b+c = 15.....i and u = b-c= 5....ii
solving i and ii we get b= 10 miles/hr and c= 5 miles/hr