Annika hikes at a constant rate of 12 minutes per kilometer. She has
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18 Apr 2021, 03:15
Intuitively, if she has traveled from point S ( start ) to the point E (east ), at the rate of 12 km per minute, then, according to the
formula W = RT, we get 12 = R(1) which in turn gives us R = 1/12.
So, for travelling 2.75 km, she would've taken T = 12*2.75 = 33 minutes.
If she has to return in 45 mins, the time she takes to return the distance she has so far traveled is 33.Thus she has 45-33 = 12 minutes left. she still has to move East and then return back. therefore on dividing this 12/2= 6.
So, she goes east for six minutes and comes back again for six minutes and then takes the 33 minutes to travel back the 2.75 km.
Therefore, to calculate the total distance she traveled to east, just add 2.75 + ( distance traveled in 6 minutes)
Distance traveled in 6 minutes = 6/12 = 0.5.
Thus the answer is, 2.75+0.5 = 3.25 which is C.