frank liked to buy packs of baseball cards. on 3 different days, he bought 3 packs. on 3 other days, he bought 4 packs each day. After that he splits his packs with his 2 brothers. How many packs will they each have. Choose the expression that best matches this situation.

First, frank buys 3 packs on 3 different days, so in those first 3 days he buys:

3*3 = 9 packs.

Then on other 3 days he buys 4 packs each day, so he has:

3*4 = 12 packs.

In total he haves:

9 + 12 = 21 packs.

Now he divides the packs with his 2 brothers (So we divide 21 packs between 3 people)

Then each brother gets:

N = 21/3 = 7 packs each.