下面各题你认为怎样简便就怎样算.
来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/05/13 16:18:58
(1)
5 7 ÷(5-3× 2 3 ), = 5 7 ÷(5-2), = 5 7 ÷3, = 5 7 × 1 3 , = 5 21 ; (2)84×0.25+ 1 4 ×16, =84×0.25+0.25×16, =(84+16)×0.25, =100×0.25, =25; (3)48×( 1 3 - 1 2 + 1 4 ), =48× 1 3 -48× 1 2 +48× 1 4 , =16-24+12, =4; (4) 1 2 ÷ 2 5 - 2 3 × 7 10 , = 1 2 × 5 2 - 2 3 × 7 10 , = 5 4 - 7 15 , = 47 60 ; (5)7.8×101, =7.8×(100+1), =780+7.8, =787.8; (6)(1-0.8× 3 4 )÷ 4 5 , =(1-0.6)÷ 4 5 , =0.4× 5 4 , =0.5. |