Question

a) \(\dfrac{2}{4}\)+\(\dfrac{13}{16}\):\(\dfrac{39}{2}\)

b) \(\dfrac{1}{2}\)x\(\dfrac{3}{5}\)+\(\dfrac{1}{2}\)x\(\dfrac{12}{5}\)

Answer 1

có dc tính nhanh ko:)?

Answer 2

a) =  2/4 + 1/24 = 13/24

b) = 1/2 x ( 3/5 + 12/5 ) = 1/2 x 3 = 3/2

Answer 3

2/4 + 1/24 = 13/24

3/10 + 6/5 = 3/2

Answer 4

1/2+1/16=9/16

1/2.(3/5+12/5)=1/2.3=3/2

Answer 5

=2/4+13/16x2/39

=2/4+1/24

=12/24+1/24

=13/24

b/=3/10+12/10=15/10

=3/2

Answer 6

`a) 2 / 4 + 13 / 16 : 39 / 2`

`= 2 / 4 + 13 / 16 . 2 / 39`

`= 2 / 4 + [ 13 xx 2 ] / [ 2 xx 8 xx 13 xx 3 ]`

`= 2 / 4 + 1 / 24`

`= 12 / 24 + 1 / 24 = 13 / 24`

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`b) 1 / 2 xx 3 / 5 + 1 / 2 xx 12 / 5`

`= 1 / 2 xx ( 3 / 5 + 12 / 5 )`

`= 1 / 2 xx 15 / 5`

`= 1 / 2 xx 3`

`= 3 / 2`