Question

. A soft serve ice cream dispenser keeps a record of how many guest choose chocolate, vanilla, or swirl ice cream cones. On Friday night the machine showed that it served a total of 640 guest. Thirty percent of the sales were chocolate, of the sales were vanilla, and the remaining sales were swirl ice cream cones. How many customers chose swirl ice cream cones?

Answer 1

In this problem

we have that

640 guests represent 100% of the sales

so

we have

30% =30/100=3/10 -----> chocolate

3/8 ----------------> vanilla

x -------> swirl ice cream cones

so

x+(3/8)+(3/10)=1

solve for x

x+(15+12)/40=1

x+27/40=1

x=1-27/40

x=13/40

Applying proportion

640/1=N/(13/40)

solve for N

N=(13/40)*640

N=208

therefore

the answer is 208 customers