Question

numa escola de 900 alunos 42% são rapazes. Calcule o número de rapazes​

Answer 1

900------100%

x----------42%

100x=37800

x=37800/100

x=378

Answer 2

$\sf\dfrac{900}{x}=\dfrac{100\%}{42\%}$

$\sf100x=37800$

$\sf x=\dfrac{37800}{100}$

$\boxed{\boxed{\sf x=378}}$