Question

va rog a si b :(( am nevoie urgent.

Answer 1

Răspuns

Explicație pas cu pas:............................

Answer 2

Răspuns

29 / 210 ; 77 / 36

Explicație pas cu pas:

a ) ( 1 / 21 + 1 / 14 ) - ( 1 / 35 - 1 / 42 ) + ( 1 / 14 - 1 / 21 ) =

= ( 2 + 3 / 42 ) - ( 6 - 5 / 210 ) + ( 3 - 2 / 42 )

= 5 / 42 - 1 / 210 + 1 / 42

= ( 25 - 1 + 5 ) / 210

= ( 24 + 5 ) / 210

= 29 / 210

b ) ( 4  1 / 6 - 1  1  / 9 ) - ( 11 / 8 - 7 / 24 ) + ( 1 / 10 + 1 / 15 ) =

= ( 25 / 6 - 10 / 9 ) - ( 11 / 8 - 7 / 24 ) + ( 1 / 10 + 1 / 15 )

= ( 75 - 20 )  / 18 - ( 33 - 7 ) / 24 + ( 3 + 2 ) / 30

= 55 / 18 - 26 / 24 + 5 / 30

= 55 / 19 - 13 / 12 + 1 / 6

= ( 110 - 39 + 6 ) / 36

= ( 71 + 6 ) / 36

= 77 / 36