300×5= 7200÷9= 63+37+56=1600÷4= 180×2= 200÷50÷4=23×30= 560÷8= 360﹣360÷4=
524﹣(124﹣87)
94×56.87+94×43.48+6×100.35.
计算(能简算的要简算)12.5×8×4×0.25 .
9999×7+1111×37.
(1)26.86×25.66﹣16.86×25.66 (2)52.3×0.68+3.2×5.23(3) (4)99+99×99+99×99×99.