Question

Calculati termenul necunoscut din: a) 5/x=0,20; b) x/9=4,2 c) 11/x=1,4; d) 9/x=4; e) 8,3/5=x; f) 6,(4)/x=8 VA ROOOG!!!

Answer 1

a) 5/x=0,20
5/x = 20/100=1/5
x = 5×5 = 25

 b)    x/9=4,2 ⇒ x = 9×4,2= 37,8

 c) 11/x=1,4  
11/x = 14/10  ⇒ x = ( 10 · 11) /14 = 110/14 =55/7 = 7,85

d)   9/x=4 ⇒ x = 9/4= 2,25

e)   8,3/5=x ⇒ x = 8,3/5= 1,66

 f)    6,(4)/x=8
6,(4) = (64-6)/9 = 58/9
58/9 : x=8
58/9 × 1/x=8
58/9 x = 8 ⇒ 8×9 x = 58 ⇒ 72 x = 58 ⇒ x =58/72= 0,80(5)