a) numarul total va fi egal cu numerele de bilete vandute in fiecare zi adunate
adica 190 de bilete
b) aici ai asa:
[tex]x\% \times 190 = 30 \\ \frac{x}{100} \times 190 = 30 \\ \frac{x}{10} \times 19 = 30 \\ \frac{x}{10} = \frac{30}{19} \\ 19x = 300 \\ x = 15.78[/tex]
c) medie aritmetica
[tex] \frac{50 + 40 + 20 \times 3 + 10 + 30}{7} = \frac{190}{7} = 27[/tex]
d) probabilitate
total =190
favorabil= 20
probabilitate=
[tex] \frac{20}{190} = \frac{2}{19} [/tex]
e)
[tex]100 \times 15 + 90 \times 20 = 3300lei[/tex]
