Question

Qual deve ser o capital aplicado a uma taxa de juro simples de 24% a.a. para que em 6 meses renda R$ 425,00 de juro?

Answer 1

i = 24% a a = 24//12 = 2% a m = 2/100 = 0,02

t = 6 m

j = 425

j = cit

425 = C * 6 * 0,02

425 = 0,12 C

C = 425/ 0,12

C = 3 541,70 *****

Answer 2

$\sf\large \boxed{\boxed{\tt J = C \cdot i \cdot t}}$

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$\sf \displaystyle 425\:=\:C\:\cdot 0,\:25\:\cdot \left(\frac{1}{2}\right)\\\\\\\sf \boxed{\star \sf \ {Troque \:os \:lados} }\\\\\\\sf C\cdot \:0.25\left(\frac{1}{2}\right)=425\\\\\\\sf C\frac{0.25}{2}=425\\\\\\\sf 2C\frac{0.25}{2}=425\cdot \:2\\\\\\\sf 0.25C=850\\\\\\\sf \frac{0.25C}{0.25}=\frac{850}{0.25}\\\\\\\\\large \to \boxeed{\boxed{\sf C=3400}}$