Describe a situation that can be represented by adding a negative number and a positive number

Question

Describe a situation that can be represented by adding a negative number and a positive number 

Answer 1

If you have $10 (+) and you owe your friend $3 (-), then after you pay your debt you have $7 (+) left.

10+(-3)=7

The temperature is -9º in the morning and the temperature goes up 5º by noon. What is the temperature at noon ?

-9+5=-4

Answer 2

If you think in terms of money then you can come up with hundreds of examples.  For instance, if you borrow money from a friend to go to the movies, you now owe your friend that money. 

 

Let's say that the movie was $10.00.  You are currently moving to the left of zero on the number line because you are in a negative balance.  So you could represent that as -10. 

 

If you washed your family car and earned $10.00 for the job then you would pay back that money to your friend.  And you would be moving to the right on the number line. So, 10.

 

Your expression could look like: -10 + 10

 

You would have a ZERO balance owed to your friend for the movie because you paid back what was owed.

Answer 3

Frank made a bet with Cecil. The bet was that the Seattle Seahawks would lose Sunday's football game against the visiting Chicago Bears. Frank lost but not as bad as the Bears did (0-23), he only lost $10 (-$10). Somehow, he was still feeling lucky, so he went double-or-nothing on his next bet that the Broncos would defeat Detroit and won $20 (+$20).

 

Calculating his net earnings on Sunday, Frank lost $10 then won $10: -$10 + $20 = $10.

 

Hope this helps!

 

Neal