Question

0.25×34＋四分之一＋65÷4 20×五分之二-0.27÷三分之一＋6.8 546-398 457＋199

（七分之三加二十一分之五＋十四分之二）×21 2.2×101 5.4×99×5.4
32×0.125×25 4.27×八分之一＋4.73÷8＋八分之一 （10.25-5.72-4.28）×二十五分之十六
怎么简便

Answer 1

0.25×34＋四分之一＋65÷4
=0.25×34+0.25+0.25×65
=0.25×(34+1+65)
=0.25×100
=25

20×五分之二-0.27÷三分之一＋6.8
=8-0.27×3+6.8
=14.8-0.81
=14.8-0.8-0.01
=14-0.01
=13.99

546-398
=546-400+2
=146+2
=148

457＋199
=457+200-1
=657-1
=656

（七分之三加二十一分之五＋十四分之二）×21
=21×3/7+21×5/21+21×2/14
=9+5+6
=20

2.2×101
=2.2×（100+1）
=2.2×100+2.2
=220+2.2
=222.2

5.4×99+5.4
=5.4×(99+1)
=5.4×100
=540

32×0.125×25
=8×0.125×4×25
=1×100
=100

4.27×八分之一＋4.73÷8＋八分之一
=4.27×1/8+1/8×4.73+1/8
=1/8×(4.27+4.73+1)
=1/8×10
=5/4

（10.25-5.72-4.28）×二十五分之十六
=(10.25-10)×16/25
=0.25×16/25
=0.16

Answer 2

0.25×34＋四分之一＋65÷4
=1/4×34+1/4×1+1/4×65
=1/4×(34+1+65)
=1/4×100
=25
20×五分之二-0.27÷三分之一＋6.8
=8-0.91+6.8
=13.89
546-398
=546-(400-2)
=148
457＋199
=457+200-1
=456
（七分之三加二十一分之五＋十四分之二）×21
=3/7×21+5/21×21+1/7×21
=9+5+3
=17
2.2×101
=2.2×(100+1)
=220+2.2
=222.2
5.4×99×5.4
=5.4×5.4×(100-1)
=29.16×(100-1)
=2916-29.16
=2886.84
32×0.125×25
=8×0.125×4×25
=1×100
=100
4.27×八分之一＋4.73÷8＋八分之一
=(4.27＋4.73＋1)×1/8
=10×1/8
=1.25
（10.25-5.72-4.28）×二十五分之十六
=[10.25-(5.72+4.28)×16/25
=(10.25-10)×16/25
=1/4×16/25
=4/25

Answer 3

（七分之三加二十一分之五＋十四分之二）×21=(18/42+10/42+6/42)*21=34/2=17

Answer 4

将算式中相同项单独拿出来即可