Question 1021974
Write an equation for each statement
:
the ratio of small to medium cones sold was 3 to 1, 
{{{s/m}}} = {{{3/1}}}
cross multiply 
s = 3m
:
and the ratio of medium to large cones sold was 9 to 25.
{{{m/L}}} = {{{9/25}}}
9L = 25m
L = {{{25/9}}}m

 the class sold 27 cones.
s + m + L = 27
Replace s and L
3m + m + {{{25/9}}}m = 27
4m + {{{25/9}}}m = 27
multiply equation by 9 to get rid of the denominator
36m + 25m = 243
61m = 243
m = 243/61
m = 3.98, not an integer, something wrong with this problem, perhaps 27 cones is not correct.
If this is the case, just replace 27 with correct value and proceed. 
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A. How many small cones were sold?
B. How many large cones were sold?
C The class sold small cones for $1.50, medium cones for $2.00, and large cones for $2.50. How much money did the class raise?