D = RT
Where
D is distance
R is speed
T is time
Distance of student 1:
[tex]D_1=2t[/tex]Distance of student 2:
[tex]D_2=3t[/tex]Now,
When they meet, their distance would total 100, so we can write:
[tex]D_1+D_2=100[/tex]We can also write:
[tex]D_1=100-D_2[/tex]