Question

Bài 3: Quy đồng mẫu số các phân số sau:

a) 1/2; 23; 3/5  b) 1/5 ; 2/6 ; 11/30

Answer 1

a, Mẫu số chung : 30

\(\dfrac{1}{2}=\dfrac{15}{30}\\ \dfrac{2}{3}=\dfrac{2.10}{30}=\dfrac{20}{30}\\ \dfrac{3}{5}=\dfrac{3.6}{5.6}=\dfrac{18}{30}\)

b, Mẫu số chung : \(30\)

Giữ nguyên :\(\dfrac{11}{30}\)

\(\dfrac{1}{5}=\dfrac{6}{30}\\ \dfrac{2}{6}=\dfrac{2.5}{6.5}=\dfrac{10}{30}\)

Answer 2

a: 1/2=15/30

2/3=20/30

3/5=18/30

b: 1/5=6/30

2/6=10/30

11/30=11/30

Answer 3

`a, 1/2 = (1xx15)/(2xx15) = 15/30`

` 2/3 = (2xx10)/(3xx10) = 20/30`

` 3/5 = (3xx6)/(5xx6) = 18/30`

`b, 1/5 = (1xx6)/(5xx6) = 6/30`

`2/6 = (2xx5)/(6xx5) = 10/30`

Answer 4

`a)`

`MSC : 30`

`1/2=( 1xx15)/(2xx15)=15/30`

`2/3=( 2xx10)/(3xx10)=20/30`

`3/5 =(3xx6)/(5xx6)=18/30`

`b)`

`MSC:30`

`11/30` giiuwx nguyên

`1/5=(1xx6)/(5xx6)=6/30`

`2/6=(2xx5)/(6xx5)=10/30`