Two people are 3SolutionDistanced equals Rater times Timet o

Two people are 3

Solution

Distance(d) equals Rate(r) times Time(t) or d=rt; r=d/t and t=d/r
Let r=rate of slower walker
Then r+1=rate of faster walker
Distance slower walker walks=r*(1/2)
Distance faster walker walks=(r+1)*(1/2)
Now the above two distances must add up to 3.5 mi, so:
0.5r+0.5(r+1)=3.5 get rid of parens
0.5r+0.5r+0.5=3.5 subtract 0.5 from each side
0.5r+0.5r+0.5-0.5=3.5-0.5 collect like terms
r=3 mph----------------------rate of the slower walker
In 1/2 hour the slower walker will walk (1/2)*3=1.5 mi
r+1=3+1=4 mph-----------------rate of faster walker
CK
0.5*3+0.5*4=3.5
1.5+2=3.5
3.5=3.5