Train a and b speed math help
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Train a and b speed math help

[From: ] [author: ] [Date: 12-07-16] [Hit: ]
so I hope theyre right. Good luck!......

Because d = r*t, and the times are the same in the problem, let's solve for t:

Divide each side by r, and you get:

t = d/r

Now, we know the times are the same, so the equation is:

tA = tB

Unfortunately, we don't have actual numbers for the times, but we do have distances and rates, and we know that time = distance/rate from above. So, let's make the equation:

dA/rA = dB/rB

From the problem, the variables are:

dA = 160
dB = 120
rA = rB+20
rB = ?

Plug those into your equation:

160/(rB+20) = 120/rB

Now there's only one variable, so solve for the rate of train B:

160rB = 120rB + 2400

40rB = 2400

rB = 60 mph

We know from above that rA = rB + 20, so rA = 80 mph

Always set up the variables to figure out what you're given in the problem, then adjust the distance formula (d = r*t) from there so it will work for your problem!

To be perfectly honest, the second one has me stumped! It seems like other people have given you answers, though, so I hope they're right. Good luck!
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