4. Efectuați:
[tex]a) \frac{12}{20} \times \frac{4}{6} \times \frac{5}{22} [/tex]
[tex]b) \frac{22}{36} \times \frac{1}{3} \times \frac{81}{11} [/tex]

[tex] c) \frac{50}{26} \times \frac{1}{1 } \times \frac{2}{15} [/tex]
[tex] d)3 \times \frac{1}{4} \times 2 \times \frac{11}{14} [/tex]
Dau coroană ​