3-5 Multiplying & Dividing Integers with Models

The water level dropped three inches every week for four weeks. By how much did the water level change?

(a)  

Answer explanation

Dropped is a negative action there for it is -3. This action happens 4 weeks in a row. Therefore the equation is -3 x 4.

Tags

CCSS.7.NS.A.3

A checking account is overdrawn (overdrawn= spending more money than you actually have in your account) by $10 on both Friday & Saturday. By how much was the account overdrawn?

(a)  

Answer explanation

The account was overdrawn $10 per day. Overdrawn is a negative action. (-10) They overdrew the account two days, Friday and Saturday.

-10 x 2

Tags

CCSS.7.NS.A.3

^{-20 divided by 4}

(a)  

Answer explanation

negative and a positive = negative

Tags

CCSS.7.NS.A.2A

CCSS.7.NS.A.2B

Answer explanation

negative x positive = negative

Tags

CCSS.7.NS.A.2A

CCSS.7.NS.A.2B

Answer explanation

positive divided by a positive = positive

Tags

CCSS.3.OA.B.5

Which expression does this model represent?

Answer explanation

1. Count how many counters you have in all.

2. See if they are negative or positive.

3. How many groups where made in all?

Tags

CCSS.7.NS.A.2A

CCSS.7.NS.A.2B

Which expression does this model represent?

Tags

CCSS.7.NS.A.2A

CCSS.7.NS.A.2B

Which expression is being modeled?

Answer explanation

1. Are your counters negative or positive? Since they are all negative. Your answer must be negative.

* a negative x a positive

2. Count your columns

3. Count your rows.

Tags

CCSS.7.NS.A.2A

Which expression does this model represent?

Answer explanation

1. Count your hops.

2. How long are your hops.

3. is it going right or left.

remember left is negative and right is positive.

Tags

CCSS.7.NS.A.2A

CCSS.7.NS.A.2B

Which model is being represented by this model?

Answer explanation

1. Which direction are your hops going? Left (negative)

2. How many hops?

3. How long are your hops?

Tags

CCSS.7.NS.A.2A

CCSS.7.NS.A.2B