Single digit addition and subtraction
6+7=?
13
300+200=
500
8+8=
16
A firefighter station has 25 firefighters. After some firefighters left for a rescue, there were only 18 firefighters left at the station. How many firefighters left for the rescue?
7 men left for the rescue
25-18= 7
9+0=?
9
37-9=?
28
60-29=?
31
The spaceship has 6 astronauts from the United States and 4 astronauts from Russia. How many astronauts are there in total on the spaceship?
10 ships total
6+4=10
5-4=
1
423-164=?
259
12+22=?
34
There were 60 children in a park. After the park ranger asked 15 children to leave because of a thunderstorm warning, how many children are left in the park?
45 children left at the park
60-15=45
-3+8=?
Positive 5
you can tell whether the answer is a positive or a negative by looking at the largest number. 8 is more than 3, so therefore is positive 5.
849+809
1,658
92-17
75
On a trip to Mars, the spaceship used 200 gallons of fuel on the first day and 250 gallons on the second day. How many gallons of fuel did the spaceship use in total?
450 gallons of fuel total
250+200=450
-9-8=?
Negative -17
When you have two negatives the answer will always be negative.
310-___=75
235
92+92=
184
Detective Johnson has 30 cases to solve. After solving 12 cases, how many cases does Detective Johnson still have to solve?
18 more cases
30-12=18
12+18=30