It’s 54 because I did the math to get the answer
Answer:
Step-by-step explanation:
this is confusing b/c they are asking about two trains traveling at differnt speeds, but.. if you put the speeds together and make one train... imaginary.. ofc... traveling at the speed of both trains combined... when will it be 50 miles from the station?
maybe you can solve that? I'll solve it below.. but.. if you can.. try it now, on your own
below is my answer... don't look until you have solved yours :P
80+70= 150kph
when will this have traveled 50Km?
you may be able to see that it will take 1/3 of an hour to travel 50 km
so 60 minutes times 1/3 = 20 minutes :)
Answer: (D) 
Explanation:

Just a note on writing down these expressions: I recommend using parentheses whenever you can to avoid misinterpretation. An expression 1/x-1/y / 1/x+1/y could be interpreted by someone as 1/x-(1/y / 1/x)+1/y, which is a different thing.
Answer:
9
Step-by-step explanation:
so we know that its a right triangle and 8 and
are not the hypotenuse.
the equation for this is
+
=
with c being the hypotenuse.
+
=
64+17=
81=c
=c
9=c