Question

Lily wants to buy 4 pounds of cereal for her camping trip. The boxes are each 18 ounces. According to the number line, how many boxes will she need to buy to have at least 4 pounds?

4 boxes
2 boxes
5 boxes
3 boxes

Answer 1

4 Boxes

Explanation:

Given: We know that each box has 18 ounces of cereal.

Note: 1 lb = 16 oz

Solution:

18 oz = 18oz*(1lb/16oz) = (18/16) lb

→ Each box has (18/16) pounds of cereal.

Question → How many boxes we need to buy if we want to have at least 4 pounds of cereal?

If we buy x boxes, we will have x*(18/16) lb boxes of cereal.

Find x :

x*(18/16) lb = 4lb

x= 4*(16/18) = 3.56

Can't have a 0.56 of a box, thus we should round our number up to the next whole number, then we get:

x = 4

Hence, Lily should buy 4 boxes.

[RevyBreeze]

Answer 2

Answer: 4 boxes.

Explanation:

We know that each box has 18 ounces of cereal.

We know that:

1 lb = 16 oz

Then:

1 = (1lb/16oz)

Then we can write:

18 oz = 18oz*(1lb/16oz) = (18/16) lb

This means that each box has (18/16) pounds of cereal.

Now, how many boxes we need to buy if we want to have at least 4 pounds of cereal?

If we buy N boxes, we will have N*(18/16) lb boxes of cereal.

Let's find N such that:

N*(18/16) lb = 4lb

N = 4*(16/18) = 3.56

But you can not have a 0.56 of a box, so we should round our number up to the next whole number, then we get:

N = 4.

She should buy 4 boxes.