Question

  a)   7/15 + 22/12 + 8/15 + 2/12                      b)  9/7 + 16 / 20 + 4 / 20 + 5/7

tính thuận tiện

Answer 1

a. (7/15 + 8/15) + (22/12 + 2/12) 

= 1 + 24/12

= 1 + 2

=3

b.(9/7 + 5/7) + (16/20 + 4/20)

= 14/7 + 20/20

= 2 + 1

= 3

Answer 2

\(a,\dfrac{7}{15}+\dfrac{22}{12}+\dfrac{8}{15}+\dfrac{2}{12}\\ =\left(\dfrac{7}{15}+\dfrac{8}{15}\right)+\left(\dfrac{22}{12}+\dfrac{2}{12}\right)\\ =\dfrac{15}{15}+\dfrac{24}{12}\\ =1+2\\ =3\\ b,\dfrac{9}{7}+\dfrac{16}{20}+\dfrac{4}{20}+\dfrac{5}{7}\\ =\left(\dfrac{9}{7}+\dfrac{5}{7}\right)+\left(\dfrac{16}{20}+\dfrac{4}{20}\right)\\ =\dfrac{14}{7}+\dfrac{20}{20}\\ =2+1\\ =3\)

Answer 3

a, (7/15+8/15)+(22/12+2/12)

=1+2=3

Answer 4

 a)   7/15 + 22/12 + 8/15 + 2/12      

( 7/15 + 8/15) + ( 22/12+ 2/12)

= 1 + 2

= 3

 

b)  9/7 + 16 / 20 + 4 / 20 + 5/7

( 9/7 + 5/7) + ( 16/20 + 4/20)

= 2 + 1

= 3

 

Answer 5

b,(9/7+5/7)+(16/20+4/20)

= 1+1=2

Answer 6

a)=3

b)=3

Answer 7

a)\(\dfrac{7}{15}+\dfrac{22}{12}+\dfrac{8}{15}+\dfrac{2}{12}=\left(\dfrac{7}{15}+\dfrac{8}{15}\right)+\left(\dfrac{22}{12}+\dfrac{2}{12}\right)=1+2=3\)

b) \(\dfrac{9}{7}+\dfrac{16}{20}+\dfrac{4}{20}+\dfrac{5}{7}=\left(\dfrac{9}{7}+\dfrac{5}{7}\right)+\left(\dfrac{16}{20}+\dfrac{4}{20}\right)=2+1=3\)

Answer 8

a. (7/15 + 8/15) + (22/12 + 2/12) = 1 + 24/12= 1 + 2=3

b.(9/7 + 5/7) + (16/20 + 4/20)= 14/7 + 20/20= 2 + 1= 3

Answer 9

a)   7/15 + 22/12 + 8/15 + 2/12 

(7/15 + 8/15) + (22/12 + 2/12) 

= 1 + 24/12

= 1 + 2

=3

 

 b)  9/7 + 16 / 20 + 4 / 20 + 5/7

(9/7 + 5/7) + (16/20 + 4/20)

= 14/7 + 20/20

= 2 + 1

= 3

Answer 10

a,(7/15+8/15)+(22/12+2/12)

=1+2=3