幼兒珠算初級階段練習題：4以內(nèi)直加直減練習

1+2+1= 3-1+2= 2+1-1+2-3= 1+3-2+2-1= 11+22=
    4-2+1= 2-1+1= 4-3+2-1+2= 1-1+3-2+3= 33-22=
    3+1-2= 2+2-3= 2-2+4-3+1= 3+1-2-1+2= 22+11=
    2-1+2= 4-3+2= 4-2+1-2+3= 1+3-2+1-1= 33-11=
    4-2+2= 1+2-2= 4-1-2+1+2= 3-1+2-2+1= 44-33=
    3+1-1= 2-1+3= 1+3-2+1-2= 3+1-3+2-1= 11+33=
    4-2-1= 4-3+1= 4-3+1-1+2= 1+2-2+3-1= 22-22=
    3-2+3= 3-1+1= 2-1+3-2+2= 2+1-2+1-1= 44-22=
    4-3+2= 1+2-1= 1+3-3+1+2= 3+1-2-1+1= 11+11=