①
⑵
③
④
①1-+
②+++
③-(+)
④+-
①15 -4.25-5
②19.82-6.57-3.43
③4.6+3 +6 +5.4
④4 +2.25+5 +7
⑤9.63÷2.5÷4
⑥8.37-3.25-(1.37+1.75)
①21×16÷14+76
②9- -
③ ×0.8×12.5
④48×( + - )
⑤7.6×9.4- +7.6×1.6
⑥ ×[ ÷(0.4- )]