options: Solve two-step word problems using the four operations. Represent these problems using equations with a letter standing for the unknown quantity. Assess the reasonableness of answers using mental computation and estimation strategies including rounding. (This standard is limited to problems posed with whole numbers and having whole number answers; students should know how to perform operations in the conventional order when there are no parentheses to specify a particular order (Order of Operations).)

Identify arithmetic patterns (including patterns in the addition table or multiplication table), and explain them using properties of operations. For example, observe that 4 times a number is always even, and explain why 4 times a number can be decomposed into two equal addends.
problem_activity: Problem 1
Katia and Gerard are stocking shelves at the grocery store. Katia stocks 3 shelves with 7 boxes of cereal on each shelf. Gerard stocks 7 shelves with 3 boxes of cereal on each shelf.
Katia says they put the same number of cereal boxes on each shelf. Gerard says they didn’t, since they stocked a different number of boxes on each of a different number of shelves. Who do you agree with, Katia or Gerard? Explain.
Problem 2
Fill in the facts you know on the multiplication table below.
| **           ×          **  | **           1          ** | **           2          ** | **           3          ** | **           4          ** | **           5          ** | **           6          ** | **           7          ** | **           8          ** | **           9          ** | **           10          ** |
|-----------------------------|----------------------------|----------------------------|----------------------------|----------------------------|----------------------------|----------------------------|----------------------------|----------------------------|----------------------------|-----------------------------|
| **           1          **  |                            |                            |                            |                            |                            |                            |                            |                            |                            |                             |
| **           2          **  |                            |                            |                            |                            |                            |                            |                            |                            |                            |                             |
| **           3          **  |                            |                            |                            |                            |                            |                            |                            |                            |                            |                             |
| **           4          **  |                            |                            |                            |                            |                            |                            |                            |                            |                            |                             |
| **           5          **  |                            |                            |                            |                            |                            |                            |                            |                            |                            |                             |
| **           6          **  |                            |                            |                            |                            |                            |                            |                            |                            |                            |                             |
| **           7          **  |                            |                            |                            |                            |                            |                            |                            |                            |                            |                             |
| **           8          **  |                            |                            |                            |                            |                            |                            |                            |                            |                            |                             |
| **           9          **  |                            |                            |                            |                            |                            |                            |                            |                            |                            |                             |
| **           10          ** |                            |                            |                            |                            |                            |                            |                            |                            |                            |                             |
Problem 3
Solve.
a.
$$4 \times 8 =a $$
b.
$$18 = b \times 6$$
c.
$$c= 35 \div 7$$
d.
$$9 = 18 \div d$$


correct_option_index: 1