Question

Ma gandesc la un nr. Adun 80 ,apoi adun 50 si obtin 100 . La ce nr. m-am gandit?

Answer 1

Notam cu a numarul
a + 80+50 = 100
a + 130 =100
a = 100-130
a = - 30

Verificare:
130-30 = 100

Answer 2

x+80+50=100

x+130=100

x=100-130

x= -30

proba 80+50-30=100