Question

dau coroană + 55 puncteee va rog repedeee

Answer 1

a)   2 / 5 ×  7 / 3 - 4 / 5 = 14 / 15 - 4 / 5 = 14 / 15 - 12 / 15 = 2 / 15

b)   3 / 4 ×  5 / 2 + 5 / 6 = 15 / 8 + 5 / 6 = 45 / 24 + 20 / 24 = 65 / 24

c)     7 / 2 ×  1 / 3 - 5 / 12 = 7 / 6 - 5 / 12 = 14 / 12 - 5 / 12 = 9 / 12 = 3 / 4

d)   2 / 5 - 12 / 5 × ( - 2 / 27 ) = 2 / 5 + 24 / 135 = ( 54 + 24 ) / 135 =

= 78 / 135 = 26 / 45

e)   7 / 3 × ( - 9 / 14 ) - 7 / 9 = - 3 / 2 - 7 / 9 = - 27 / 18 - 14 / 18 = - 41 / 18

f)   ( - 3 / 10 ) × 5 / 6 + 9 / 5 = - 5 / 20 + 36 / 20 = 31 / 20 = 1 intreg 11/ 20

g)   11 / 12 - ( - 16 / 15 ) ×  ( - 5 / 12 ) = 11 / 12 - 4 / 9 =

= 33 / 36 - 16 / 36 = 17 / 36

h)   ( - 21 / 25 ) × ( - 5 / 14 ) -  17 / 15 = 3 / 10 - 17 / 15 =

= 9 / 30 - 34 / 30 = - 25 / 30 = - 5 / 6