52×a×20=52×(a×20)
25×3×4×5=( )
96×35=35×
(277+174)+26=
①7400÷(25×37)
②100.1+10.82+20.8﹣90.01
③99×999+999
④48×125×25
⑤137.5﹣(42.5﹣37.5﹣51.5)
⑥4080÷[(650﹣648)×30]
34×4430×40 21×1821×3×6 14×1914×20-14
63×2060×19 72×1472×5×3 39×4139×40+39
①61.27-8.13-1.87
②3.9+4.08+1.1+5.92
③255×105-255×5
④101×77
⑤25×43×4
⑥4200÷25÷4