



 
Hi Pedro, I think the problem is this. You go to the vendor and order 4 different types. How many different choices do you have? That is how many ways can you choose 4 flavors from 15 flavors? Penny
What you did corresponds to the problem "...She spent most of the money on jewellery, keeping a quarter. Then she bought a digital camera, keeping 2/3 of the remaining money." See the difference? A way to make this more intuitive: think of really extreme proportions. Suppose she had spent 99% of her money on a camera and had $2 left: what would you do to find what she started with? Now do exactly the same thing with the numbers you were given. Good Hunting!  


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