1 ) 10+(100-n):10=19


Răspuns :

10+(100-10):10=10+90:10=10+9=19
10 + (100-n) : 10 = 19

(100 - n) : 10 = 19 - 10

(100 - n) : 10 = 9

100 - n = 9 × 10

100 - n = 90

n = 100 - 90

n = 10
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