x+2/5=1/2
x. =1/2-2/5
x. =3/10
d)2/3-x=8/21
x=2/3-8/21
x=8/21. ( cho mik đi bạn)
a) 1/3+1/6+4/3+2/3+5/6
= 2/6+1/6+8/6+4/6+5/6
= 20/6=10/3
b)5/7+x/35=4/5
x/35=4/5-5/7
x/35=8/35
=> x. =8 ( cho mik đi rồi mik lm tiếp cho)
1/3+1/6+4/3+2/3+5/6=(1/3+2/3+4/3)+(1/6+5/6)=1+1=2
5/7+×/35=4/5
=>x/35=4/5-5/7=28/35-25/35=10/35
=>x=10
×+2/5=1/2
=>x=1/2-2/5=5/10-4/10=1/10
2/3-x=8/21
=>x=2/3-8/21=14/21-8/21=6/21=2/7
bn Mai Ngọc ơi! bn tính nhầm rùi đó aq
xin lỗi nha...chỗ 1/5-2/5=1/10 nhé