Cách 1:\(\left(\frac{1}{3}+\frac{1}{5}\right)x\frac{1}{2}=\frac{8}{15}x\frac{1}{2}=\frac{4}{15}\)
Cách 2:\(\left(\frac{1}{3}+\frac{1}{5}\right)x\frac{1}{2}=\frac{1}{3}x\frac{1}{2}+\frac{1}{5}x\frac{1}{2}=\frac{1}{6}+\frac{1}{10}=\frac{4}{15}\)
giai bang hai cach; (5/6-1/2):2/3 va bai (3/4+1/2):3/5
giai ho bai giai bang hai cach: (3/4+1/2):3/4
tinh bang hai cach a)3/4 x 1/2 x 2
cach 1 : .....................................................
cach 2 : .....................................................
b) (3/4 + 1/2) x 5?7
cach 1 : .................................................................
cach 2 : .................................................................
giai bang hai cach [1/3+1/5]x1/4
tinh bang hai cach
3/22 x 3/11 x 22
[1/2 + 1/3] x 2/5
tinh gia tri bieu thuc sau bang hai cach:
a,1/2 x 1/3+1/3 x1/5
b,{2/5+3/10} x 1/2
giai bang hai cach
a 1215 : x : 5 = 3
b 1215 : x : 5 = 3
bai 1 : tinh bang hai cach
a) 3/22 x3/11 x22 =??
b)( 1/2 + 1/3 ) x2/5 =???
c)
3/5 x 17/21 + 17/21 x 2/5 =???
1+2-3+4-5+6-7+8-9+10...19+20 tinh nhanh bang bao nhieu giai thich cach lam
