#9
|
|||
|
|||
Re: Is this word problem solvable?
Algebra for those who can't follow the shortcut:
v = speed that canoeist paddles s = speed of stream = speed of log t = time canoeist spent traveling downstream v-s = speed of canoeist going upstream v+s = speed of canoeist going downstream d1 = total distance traveled by canoeist upstream d1 = 2 miles + (v-s)(1 hour) = 2 + v - s d2= total distance traveled by canoeist downstream d2 = (v+s)t = vt + st We also know that the log traveled 2 miles in (t+1) hours 2 miles = s(t+1) st + s = 2 also, d2 = d1 2 + v - s = vt + st 2 + v = vt + (st + s) 2 + v = vt + 2 (from above, st + s = 2) v = vt t = 1 hour st + s = 2 s + s = 2 2s = 2 s = 1 mph |
|
|