Maria was putting together party favors for her niece's birthday party. She put three small chocolate candies and four hard candies into each bag.

1. If Maria had $10$ bags, how many candies did she use in all?

   Hint (a):

   If Maria used $7$ candies in one bag, how many candies did she need for 10 bags?

2. In order to represent the total number of candies in ten bags, we write the expression $10\left(3 + 4\right)$. What expression would we write to represent the total number of candies used if Maria had to make $12$ bags for party favors?

   Hint (b):

   Which number in the expression $10\left(3 + 4\right)$ represents the number of bags? This number needs to change to $12$.