SOLUTION: A Ice cream parlor sells a single scoop of icecream on a cone for $2.10 and each additional scoop is 65c. A Sundae shop nearby sells a double scoop on a cone for $2.25 and charges

Algebra ->  Graphs -> SOLUTION: A Ice cream parlor sells a single scoop of icecream on a cone for $2.10 and each additional scoop is 65c. A Sundae shop nearby sells a double scoop on a cone for $2.25 and charges      Log On


   

Question 996959: A Ice cream parlor sells a single scoop of icecream on a cone for $2.10 and each additional scoop is 65c. A Sundae shop nearby sells a double scoop on a cone for $2.25 and charges 70c for each extra scoop. How many total scoops of icecream would you need to buy on a single cone to make the ice cream parlor's deal a better deal.
Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
Let +n+ = number of scoops for both
ice cream parlor and sundae shop
----------------------------
This equation makes cost for 1 cone at
both places equal
+225+%2B+70%2A%28+n-2+%29+=+210+%2B+65%2A%28+n-1+%29+
+225+%2B+70n+-+140+=+210+%2B+65n+-+65+
+5n+=+210+-+65+%2B+140+-+225+
+5n+=+60+
+n+=+12+
One more scoop, or 13 scoops
makes the ice cream parlor a better deal
----------------
check:
Making the costs equal:
+225+%2B+70%2A%28+n-2+%29+=+210+%2B+65%2A%28+n-1+%29+
+225+%2B+70%2A%28+12-2+%29+=+210+%2B+65%2A%28+12-1+%29+
+225+%2B+70%2A10+=+210+%2B+65%2A11+
+225+%2B+700+=+210+%2B+715+
+925+=+925+
OK
And if there are 13 scoops:
Sundae shop:
+225+%2B+70%2A%28+n-2+%29+
+225+%2B+70%2A%28+13+-+2+%29+
+225+%2B+70%2A11+
+225+%2B+770+=+995+
-------------------
ice cream parlor:
+210+%2B+65%2A%28+n-1+%29+
+210+%2B+65%2A%28+13+-+1+%29+
+210+%2B+65%2A12+
+210+%2B+780+=+990+
-------------------
The ice cream parlor is 5 cent cheaper