Question

va rog ajutați mă la cele două ex.inafara la cele puse ​

Answer 1

Explicație pas cu pas:

3. D.6

$\dfrac{x}{1} = \dfrac{y}{2} = \dfrac{z}{5} = \dfrac{x + y + z}{1 + 2 + 5}$

$\dfrac{10}{5} = \dfrac{x + y + 10}{8} \iff 2 = \dfrac{x + y + 10}{8}$

$x + y + 10 = 16 \implies x + y = 6$

4. B.5

$a = 2 \dfrac{1}{2} = \dfrac{5}{2}$

$b = 0.5 = \dfrac{5}{10} = \dfrac{1}{2}$

$\dfrac{a}{b} = \dfrac{\dfrac{5}{2} }{\dfrac{1}{2}} = 5$