Question 1014913
Use the formula d = r*t.
Let the rate of the first person be {{{r[1]}}}, and that of the second, {{{r[2]}}}

Then in the first scenario, we have {{{9r[1] = 27 +9r[2]}}}, or {{{r[1] = 3 +r[2]}}}  (Equation 1)

In the second scenario, we get {{{3r[1] + 3r[2] = 27}}}, or {{{r[1] + r[2] = 9}}}   (Equation 2)

Substituting equation 1 into equation 2, we get {{{3 + r[2] + r[2] = 9}}}, or {{{r[2] = 3}}}kph.  Thus {{{r[1] = 6}}}kph.