Number Concepts
Number Concepts
Basic Facts and Relationships
2-Digit Addition
Subtraction and rounding
100

Is 13 even or odd?

odd

100

What is the value of the 8 in 58.

8 or 8 ones

100
1675
2000
100
Add then round to the nearest 10 56 + 34=
90
100
Subtract then round the difference to the nearest 10. 38 - 5 =
33 rounds to 30
200

What is the value of 4 in 24.
 

4 or 4 ones

200

What is another way to write the number 28?

20+8

2 tens 8 ones

twenty-eight

200
4342
4000
200
Add the round to the nearest 10 39 + 21=
60
200
Subtract then round the difference to the nearest 10. 167 - 25 =
142 rounds to 140
300

What is another way to write the number 45?

40+5  

forty-five

4 tens 5 ones

300

Count by fives. Enter the next two numbers. 

65, 70, 75, 80, 85, ___, ___ 


, 



90 , 95

300
7569
8000
300
Add then round to the nearest 100 835 + 27=
862 rounds to 900
300
Subtract then round the difference to the nearest 10. 178 - 69=
109 rounds to 110
400

Count by ones. Enter the next two numbers. 

20, 21, 22, 23, 24, 25, ___, ___


26,27

400

Is 20 even or odd?

even

400
2745
3000
400
Add and round the sum to the nearest 100. 278 + 384 =
662 rounds to 700
400
Subtract then round the difference to the nearest 100. 582 - 195 =
387 rounds to 400
500

Count by tens. Enter the next two numbers. 

30, 40, 50, 60, 70, ___ , ___


80 , 90

500

What is another way to write the number 1 ten 6 ones?

10+6

16

sixteen


500
1326
1000
500
Add the round the sum to the nearest 100. 313 + 213=
526 rounds to 500
500
Subtract then round the difference to the nearest 100. 721- 489=
232 rounds to 200
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