Question

what is a number family?? thanks..

Answer 1

A number family is an "extended family," while fact families
are "nuclear families." A number family consists of all (addition)
fact families that have the same largest number (sum). Thus, each
column below is a fact family, and all the columns constitute the "6"
number family:

6+0=6 5+1=6 4+2=6 3+3=6
0+6=6 1+5=6 2+4=6
6-6=0 6-5=1 6-4=2 6-3=3
6-0=6 6-1=5 6-2=4

Answer 2

what are the use of number family? thanks..