Question

tính
1/3+5/4          4/12-1/15         2/3x15/8         2/3:8/21

Answer 1

`1/3 + 5/4`

`= 4/12 + 15/12`

`= 19/12

__

`4/12 - 1/15`

`= 1/3 -1/15`

`= 5/15 -1/15`

`=4/15`

__

`2/3 xx 15/8`

`= (2xx15)/(3xx88)`

`= 30/24`

`=5/4`

__

`2/3 : 8/21`

`= 2/3 xx 21/8`

`= (2xx21)/(3xx8)`

`= 42/24`

`=7/4`

Answer 2

1/3+5/4=4/12+15/12

=19/12

4/12-1/15=20/60-4/60

=16/60=4/15

2/3x15/8=30/24=5/4

2/3:8/21=42/24=7/4

nhớ cho a tích nhé =)) a bị bịp nhiều rồi

 

Answer 3

\(\dfrac{1}{3}+\dfrac{5}{4}=\dfrac{4}{12}+\dfrac{15}{12}=\dfrac{19}{12}\)

_____________________________\(\dfrac{4}{12}-\dfrac{1}{15}=\dfrac{60}{180}-\dfrac{12}{180}=\dfrac{48}{180}=\dfrac{4}{15}\)

_____________________________

\(\dfrac{2}{3}\)x\(\dfrac{15}{8}\)\(=\dfrac{30}{24}=\dfrac{5}{4}\)

_____________________________

\(\dfrac{2}{3}:\dfrac{8}{21}=\dfrac{2}{3}\)x\(\dfrac{21}{8}=\)\(\dfrac{42}{24}=\dfrac{7}{4}\)

Chúc bạn học tốt:>

Answer 4

lỗi xíu thôi, sorry nha