Question

2. Tìm x, biết:

a/ \(\dfrac{x}{4}=\dfrac{16}{128}\) ; b/\(1\dfrac{5}{6}=\dfrac{-x}{5}\) ; c/ 4,25:8= -3,5 : x

Answer 1

a) \(\dfrac{x}{4}=\dfrac{16}{128}\Rightarrow x=\dfrac{4.16}{128}=\dfrac{1}{2}=0,5\)

b)\(1\dfrac{5}{6}=\dfrac{-x}{5}\\ \Leftrightarrow\dfrac{11}{6}=\dfrac{-x}{5}\Rightarrow-x=\dfrac{5.11}{6}=\dfrac{55}{6}\Rightarrow x=-\dfrac{55}{6}\)

c) \(\dfrac{4,25}{8}=\dfrac{-3,5}{x}\Rightarrow x=\dfrac{8.\left(-3,5\right)}{4,25}=-\dfrac{112}{17}\)

Answer 2

a,X/4=16/28

=»x/4=4/7

=4/7.4

=7

b,1/5/6=-x/5

-x/5=11/6

X=11/6.5

X=55/6