[tex] > \: resolucao \\ \\ \geqslant \: juros \: \: simples \\ \\ m = 4.200.00 \\ c = 1.750.00 \\ j = m - c = 4200 - 1750 = 2450 \\ i = 20\%a.a \\ \\ = = = = = = = = = = = = = = = = = \\ \\ \\ j = \frac{c \times i \times t}{100} \\ \\ 2450 = \frac{1750 \times 20 \times t}{100} \\ \\ 2450 = 1750 \times 0.2 \times t \\ \\ 2450 = 350 \times t \\ \\ t = \frac{2450}{350} \\ \\ t = 7 \\ \\ \\ resposta \: > \: \: 7 \: \: anos \\ \\ \\ \geqslant \leqslant \geqslant \leqslant \geqslant \leqslant \geqslant \geqslant [/tex]