Question

Calculati a. 1 pe 5 + 0,8 × 1 pe 4
b. 1 pe 6 + 1,2 :0,15
c. 0,3 + 0,(3) × 1 pe 2
d. 1,(3) + 0,7 × 1 pe 2​

Answer 1

Răspuns:

Explicație pas cu pas:

a) $\frac{1}{5}+0,8*\frac{1}{4} = \frac{1}{5} +\frac{8}{10} *\frac{1}{4}=\frac{1}{5} +\frac{2}{10}*\frac{1}{1}=\frac{1}{5} +\frac{1}{5}=\frac{2}{5}$

b) $\frac{1}{6} +1,2:0,15=\frac{1}{6} +\frac{12}{10} :\frac{15}{100} =\frac{1}{6} +\frac{12}{10} *\frac{100}{15}= \frac{1}{6} +\frac{4}{1} *\frac{10}{5} =\frac{1}{6} +8=\frac{49}{6}$

c) $0,3+0,(3)*\frac{1}{2}=\frac{3}{10} +\frac{3}{9} *\frac{1}{2} =\frac{3}{10} +\frac{3}{18}=\frac{27+15}{90}=\frac{42}{90}=\frac{14}{30}=\frac{7}{15}$

d) $1,(3)+0,7*\frac{1}{2}=\frac{13-1}{9}+\frac{7}{10}*\frac{1}{2}=\frac{12}{9} +\frac{7}{20}=\frac{4}{3} +\frac{7}{20}=\frac{80+21}{60}=\frac{101}{60}$