satellite73
A student has to sell 2 books from a collection of 6 math, 7 science, & 4 economics books. How many choices are possible if both books are on the same subject.

Question

satellite73
A student has to sell 2 books from a collection of 6 math, 7 science, & 4 economics books. How many choices are possible if both books are on the same subject.

anonymous · Answer

well they are adding this time because it is "or"

bahrom7893 · Answer

I thought it was 6C2*7C2*4C2 but it's 6C2+7C2+4C2

bahrom7893 · Answer

OHHHHHHHHHHHHH

anonymous · Answer

rigth
one or the other , not both together

bahrom7893 · Answer

I feel dumb...

bahrom7893 · Answer

okay so if all, then *, if or then +

anonymous · Answer

lol it is the translation that is always the hard part. computing is the easy part

anonymous · Answer

it's addition, since it's optional. . (or)

anonymous · Answer

if it was two math books AND two science book AND  two whatever, then you would multiply

bahrom7893 · Answer

ok thanks guys.

anonymous · Answer

yw