Question 190997
Let x represent the speed at which she walks, then the speed at which she jogs is x +3.
The time spent on joging is {{{2/(x+2)}}}
The time spent on walking is {{{2/x}}}.
The total time spent is {{{2/(x+2)+2/x}}}
We have already been given the total time spent: one hour.

So {{{2/(x+3)+2/x = 1}}}

Solving for x, we have
{{{2x + 2(x+3) = x(x+3)}}}  multiply both sides by x(x+3)
{{{2x + 2x + 6 = x^2 + 3x}}}
{{{4x + 6 = x^2 + 3x}}}
{{{0 = x^2 -x -6}}}
{{{x^2 -x -6 = 0}}}
{{{(x-3)(x+2)= 0}}}
So
x=3
or
x=-2(reject this negative solution)

So her walking speed is 3 miles/hour, her joging speed is x + 3 = 6 miles/hour.