Question

Train a leaves station traveling at 40 mph. Eight hours later train b leaves the same station traveling in the same direction at 60mph. how long does it take for train b to catch up to train a?

What would the formula look like to reach the desired answer?
Thank you! :)

Answer 1

`v_1=40\ mph\\v_2=60\ mph\\t_2=t_1-8\\\\v=(s)/(t)\to s=vt\\\\s_1=s_2\\\\v_1t_1=v_2t_2\\\\v_1t_1=v_2(t_1-8)`


`40t_1=60(t_1-8)\\\\40t_1=60t_1-480\\\\40t_1-60t_1=-480\\\\-20t_1=-480\ \ \ \ /:(-20)\\\\t_1=24\ (h)\\\\t_2=24-8=16\ (h)\\\\Answer:16h.`