Question

Uma conta de energia no valor de 50 reais corresponde ao consumo de 150 kw/h. Qual será o valor a ser pago se o consumo for de 300 kw/h?​

Answer 1

50 reais ----- 150 kw/h

x reais ----- 300 kw/h

150 . x = 50 . 300

150x = 15.000

x = 15.000

----------

150

x = R$ 100

Answer 2

$\large\boxed{\begin{array}{l} \rm{R\ = kw/h} \\ \\ \rm{ \dfrac{50}{x} = \dfrac{150}{300}} \\ \\ \rm{150x =300 \times 50 } \\ \\ \rm{150x = 15000} \\ \\ \rm{x = \dfrac{1500\diagup\!\!\!\!0}{15\diagup\!\!\!\!0}} \\ \\ \boxed{ \rm{x = R \ \,100}} \end{array}}$