Question 125027
{{{t = C(xy/r)}}} where {{{C}}} is the constant of proportionality. 

Substitute in {{{x=33}}}, {{{y=2}}}, {{{r=11}}} and you get:

{{{t = C(33*2/11)}}}

{{{t = C(66/11)}}}

{{{t = 6C}}} 

You already know that {{{t = -30}}} from the question, so

{{{-30 = 6C}}}

{{{C = -30/6}}}

{{{C = -5}}}.........is the constant of proportionality