Regroup the numbers in the following problems, putting the numbers that add up to 10 or a multiple of 10 in parentheses. a. 2 + 9 + 8 b. 3 + 5 + 4 + 7 c. 4 + 2 + 16 d. 31 + 4 + 9

Answer:Regrouping the numbers in the following problems, by putting the numbers that add up to 10 or a multiple of 10,

a.) 2+9+8=2+8+9 (commutative property in addition)

=10+9=19 (associative property)

b.) 3 + 5 + 4 + 7 = 3+5+7+4=3+7+5+4 (commutative property in addition)

=10+9=19

c.) 4 + 2 + 16=4+16+2 (commutative property in addition)

=20+2=22 (associative property)

d.) 31 + 4 + 9=31+9+4 (commutative property in addition)

=40+4=44 (associative property)