个直角
70-60= 59-7= 37+40= 2×4= 4×5=
1×1= 0+89= 3×2= 5×1= 18+20=
①72+25=
②89-63=
③48+27=
④27+15+43=
⑤63-29+27=
⑥70-(23+35)=