Question

[0,41(6)+0,291(6)-0,7(2)]:[-0,02(7)]=

Answer 1

0,41(6)=(416-41)/900=375/900=75/180=15/36=5/12
0,291(6)=(2916-291)/9000=2625/9000=525/1800=105/360=21/72=7/24
0,7(2)=(72-7)/90=65/90=13/18
0,02(7)=(27-2)/900=25/900=5/180=1/36

(5/12 + 7/24 - 13/18):(-1/36)=
12=2²·3
24=2³·3
18=2·3²
______
c.m.m.m.c.=2³·3²=72-numitorul comun
(5x6+7x3-13x4)/72:(-1/36)=
(30+21-52)/72:(-1/36)=
(-1/72)x(-36)=
1/2

Answer 2

0,41(6)=(416-41)/900=375/900=5/12
0,291(6)=(2916-291)/9000=2625/9000=7/24
0,7(2)=(72-7)/90=65/90=13/18
0,02(7)=(27-2)/900=25/900=1/36

[0,41(6)+0,291(6)-0,7(2)]:[-0,02(7)]=
=(5/12+7/24-13/18):(-1/36)=
=(30+21-52)/72 ×36=
=(-1/72) ×(-36)=
=1/2=0,5