Question

Calculați :
19 supra 9 - 1 supra 3 =
18 supra 11 - 3 supra 2 =
15 supra 2 - 5 supra 8 =
14 supra 11 - 1 supra 2 =
1 supra 2 + 4 supra 5 =
VĂ ROG DAU COROANĂ ȘI 12 PUNCTE .

Answer 1

$a) \frac{19}{9} - \frac{1}{3} = \frac{19}{9} - \frac{1 \times 3}{3 \times 3} = \frac{19}{9} - \frac{3}{9} = \frac{16}{9} = 1 \frac{7}{9}$

$b) \frac{18}{11} - \frac{3}{2} = \frac{18 \times 2}{11 \times 2} - \frac{3 \times 11}{2 \times 11} = \frac{36}{22} - \frac{33}{22} = \frac{36 - 33}{22} = \frac{3}{22}$

$c) \frac{15}{2} - \frac{5}{8} = \frac{15 \times 4}{2 \times 4} - \frac{5}{8} = \frac{60}{8} - \frac{5}{8} = \frac{55}{8} = 6 \frac{7}{8}$

$d) \frac{14}{11} - \frac{1}{2} = \frac{14 \times 2}{11 \times 2} - \frac{1 \times 11}{2 \times 11} = \frac{28}{22} - \frac{11}{22} = \frac{28 - 11}{22} = \frac{17}{22}$

$e) \frac{1}{2} + \frac{4}{5} = \frac{1 \times 5}{2 \times 5} + \frac{4 \times 2}{5 \times 2} = \frac{5}{10} + \frac{8}{10} = \frac{5 + 8}{10} = \frac{13}{10} = 1 \frac{3}{10}$