Vocabulary
what is addition?
combining two or more numbers
show 8 in tens blocks
[] [] [] [] [] [] [] []
490-177
313
560-283=
277
568-49=
519
what is subtraction?
taking one or more numbers away from another number
show 40 in tens blocks
[ ] [ ] [ ] [ ]
866-337=
529
401-349=
52
469+512=
981
what is regrouping?
breaking up numbers based on place value to make addition or subtraction equations easier.
show 300 in tens blocks
-------------------------
l l
l l
l l
--------------------------
-------------------------
l l
l l
l l
--------------------------
-------------------------
l l
l l
l l
--------------------------
777-168=
609
937-379=
558
161+465=
626
what is the sum?
the answer to an addition problem
show 26 in tens blocks
[ ] [ ] [] [] [] [] [] []
612-104=
508
641-465=
176
861-793
68
what does difference mean?
the answer to a subtraction equation
show 459 in tens blocks
see illustration
580-108=
472
224-57=
167
557+688
1245