Question 976927
Let's think of what happens for every {{{10000}}} servings of ice cream sold.
For every {{{10000}}} servings of ice cream sold,
{{{"45%"}}} , or {{{0.45*10000=4500}}} are chocolate,
{{{"30%"}}} , or {{{0.30*10000=3000}}} are strawberry,
and the remaining {{{"100%"-"45%"-"30%"="25%"}}} , or {{{10000-4500-3000=2500}}} are vanilla.
Of the {{{4500}}} servings of chocolate ice cream sold,
{{{"75%"}}}, or {{{0.75*4500=3375}}} were served in cones,
while the other {{{4500-3375=1125}}} were served in cups.
Of the {{{3000}}} servings of strawberry ice cream sold,
{{{"60%"}}}, or {{{0.60*3000=1800}}} were served in cones,
while the other {{{3000-1800=1200}}} were served in cups.
Of the {{{2500}}} servings of vanilla ice cream sold,
{{{"40%"}}}, or {{{0.40*2500=1000}}} were served in cones,
while the other {{{2500-1000=1500}}} were served in cups.
 
We knew, without calculations that
the probability of a serving being chocolate is {{{"45%"=0.45}}} ,
the probability of a serving being strawberry is {{{"30%"=0.30}}} , and 
the probability of a serving being vanilla is {{{"25%"=0.25}}} .
Since out of {{{10000}}} servings, there were
{{{3375}}} chocolate ice cream cones,
{{{1800}}} strawberry ice cream cones, and
{{{100}}} vanilla ice cream cones,
the total number of cones served was {{{3375+1800+1000=6175}}} .
So, the probability of a serving being a cone is {{{6175/1000=.6175="61.75%"}}} .
Of course, that makes the probability of a serving being ice cream in a cup
{{{"100%"-"61.75%"="38.25%"=0.3825}}} .
Since of the {{{6175}}} cones served,
{{{1800}}} were strawberry ice cream cones,
the probability that the ice cream was strawberry flavor, given that it was sold on a cone is
{{{1800/6175=about0.2915="29.15%"}}} (rounded).
, , and 40%,