Question

9) Calculați, folosind proprietățile înmulțirii şi împărțirii:
b) (7/4+7/8+7/12+...+7/100) : (1/4+1/8+1/12+...+1/100)=

/ = supra

Answer 1

   
[tex]\displaystyle\\ \left(\frac{7}{4} + \frac{7}{8} + \frac{7}{12} +\cdots + \frac{7}{100}\right): \left(\frac{1}{4} + \frac{1}{8} + \frac{1}{12} +\cdots + \frac{1}{100}\right) =\\\\\\ = \frac{\dfrac{7}{4} + \dfrac{7}{8} + \dfrac{7}{12} +\cdots + \dfrac{7}{100}}{\dfrac{1}{4} + \dfrac{1}{8} + \dfrac{1}{12} +\cdots + \dfrac{1}{100}}= \frac{7\left(\dfrac{1}{4} + \dfrac{1}{8} + \dfrac{1}{12} +\cdots + \dfrac{1}{100}\right)}{\dfrac{1}{4} + \dfrac{1}{8} + \dfrac{1}{12} +\cdots + \dfrac{1}{100}}=\boxed{\bf 7}[/tex]