Question 1145608
Speed of boat in still water = b
Speed of current = c
<pr>
c = (1/3)b
<pr>
Down the river:
d = d
r = b + c = b + (1/3)b = (4/3)b
t = 2
<pr>
r = d/t
(4/3)b = d/2
b = (3/8)d
<pr>
Up the river:
d = d - 16
r = b - c = b - (1/3)b = (2/3)b
t = 2
<pr>
r = d/t
(2/3)b = (d - 16)/2
b = 3(d - 16)/4
b = (3d - 48)/4
b = (3/4)d - 12
<pr>
b(down the river) = b(up the river)
(3/8)d = (3/4)d - 12
-(3/8)d = -12
(3/8)d = 12
d = 32
<pr>
From earlier:
b = (3/4)d - 12
b = (3/4)(32) - 12
b = 24 - 12
b = 12
<pr>
<b>Speed of boat in still water = b = 12 mph</b>