1-× × × × ×
①2.64×36-3.6×16.4
②1.17÷(1.17÷3.9)
③1.25×6.4×0.25
④120÷2.4+120÷1.6
①
②
③
④
①÷×
②×3.2+6.8÷
③105×(+)
④﹣+﹣
⑤6.4÷[(3﹣1.4)×]
①0.75+ + +0.375
② +9 +99 +999 +9999
③4 -(2 + )
⑤48.3-15 -4
⑥9 ×4.25+4 ÷6