2. Compatible Numbers
To find compatible numbers, look at the first
two numbers in the dividend (the larger
number in your division problem).
528 ÷ 7
You want to find two numbers that are
compatible with the number 7. A compatible
number is CLOSE to 52, one bigger and one
smaller than 52. It is also a multiple of 7.
3. Compatible Numbers
Multiples of 7
7
14
21
Use division facts for 7 and patterns to
28
find nearby compatible numbers for
528. The compatible numbers are 35
MULTIPLES of 7, which make them easy 42
to work with! 52
49
56
490 ÷ 7 = 70, 49 is smaller than 52 63
70
560 ÷ 7 = 80, 56 is larger than 52
77
The answer is between 70 and 80. 84
4. 3
252 ÷ 3 6
9
12
15
Look at first two digits: 252 18
The divisor is 3: 21
25
24
240 ÷ 3 = 80 27
252 ÷ 3 = 30
270 ÷ 3 = 90 33
36
The best estimate is between 80 and 90.
5. 368 ÷ 6
Look at first two digits: 368
The divisor is 6:
360 ÷ 6 = 60
The best estimate is 60.
**Sometimes there is only one compatible
number.
6. 3150 ÷ 9
Look at first two digits: 3150
The divisor is 9:
2700 ÷ 9 = 300
3150 ÷ 9 =
3600 ÷ 9 = 400
The best estimate is between 80 and 90.
7. 4000 ÷ 7
Look at first two digits: 4000
The divisor is 7:
3500 ÷ 7 = 500
4000 ÷ 7 =
4200 ÷ 7 = 600
The best estimate is between 500 and 600.
8. 440 ÷ 8
Look at first two digits: 440
The divisor is 8:
400 ÷ 8 = 50
440 ÷ 8 =
480 ÷ 8 = 60
The best estimate is between 50 and 60.
