Re: [obm-l] Fórmula -- Razoavelmente off tópic

["Rogerio Ponce" <abrlwsky@xxxxxxxxx>]

Ola' Ruy,
suponhamos que o valor real (a vista) do carro seja V, e que as
prestacoes mensais sejam constantes e iguais a P.
Seja "t" nossa taxa mensal de juros. Isso significa que o valor real
correspondente a uma prestacao esta' sendo dividido por (1+t) a cada
mes, de forma cumulativa.

Fazendo x = 1/(1+t), temos
V = P + P*x + P*x^2 + ... + P*x^35
ou seja,
V/P = 1+x+x^2+...+x^35 = (1-x^36)/(1-x)

Assim, dado o valor da taxa mensal (t=0.79%), temos x=1/(1+0.0079) , o
que nos da'
V/P = 31.47.

Assim, se o valor real do carro ("a vista com os todos descontos") for
V= R$ 40.000,00 , a sua prestacao mensal sera' de
40.000 / 31.47 = R$1270.90

Como calcular o valor de x a partir de V/P e' mais enrolado (o metodo
e' numerico) , eu preparei uma tabela com a correspondencia entre V/P
e a taxa de juros, para o financiamento em 36 parcelas ( com a
primeira parcela no ato da compra, e a ultima 35 meses depois )

Assim, com o valor V do carro e a prestacao mensal P , calcule V/P e
confira a taxa mensal de juros que querem lhe cobrar.

[]'s
Rogerio Ponce

35.94 : 0.01% | 35.87 : 0.02% | 35.81 : 0.03% | 35.75 : 0.04% | 35.69 : 0.05% |
35.62 : 0.06% | 35.56 : 0.07% | 35.50 : 0.08% | 35.44 : 0.09% | 35.38 : 0.10% |
35.32 : 0.11% | 35.26 : 0.12% | 35.19 : 0.13% | 35.13 : 0.14% | 35.07 : 0.15% |
35.01 : 0.16% | 34.95 : 0.17% | 34.89 : 0.18% | 34.83 : 0.19% | 34.77 : 0.20% |
34.71 : 0.21% | 34.65 : 0.22% | 34.59 : 0.23% | 34.53 : 0.24% | 34.47 : 0.25% |
34.41 : 0.26% | 34.35 : 0.27% | 34.30 : 0.28% | 34.24 : 0.29% | 34.18 : 0.30% |
34.12 : 0.31% | 34.06 : 0.32% | 34.00 : 0.33% | 33.94 : 0.34% | 33.89 : 0.35% |
33.83 : 0.36% | 33.77 : 0.37% | 33.71 : 0.38% | 33.66 : 0.39% | 33.60 : 0.40% |
33.54 : 0.41% | 33.49 : 0.42% | 33.43 : 0.43% | 33.37 : 0.44% | 33.32 : 0.45% |
33.26 : 0.46% | 33.20 : 0.47% | 33.15 : 0.48% | 33.09 : 0.49% | 33.04 : 0.50% |
32.98 : 0.51% | 32.92 : 0.52% | 32.87 : 0.53% | 32.81 : 0.54% | 32.76 : 0.55% |
32.70 : 0.56% | 32.65 : 0.57% | 32.59 : 0.58% | 32.54 : 0.59% | 32.48 : 0.60% |
32.43 : 0.61% | 32.38 : 0.62% | 32.32 : 0.63% | 32.27 : 0.64% | 32.21 : 0.65% |
32.16 : 0.66% | 32.11 : 0.67% | 32.05 : 0.68% | 32.00 : 0.69% | 31.95 : 0.70% |
31.89 : 0.71% | 31.84 : 0.72% | 31.79 : 0.73% | 31.74 : 0.74% | 31.68 : 0.75% |
31.63 : 0.76% | 31.58 : 0.77% | 31.53 : 0.78% | 31.47 : 0.79% | 31.42 : 0.80% |
31.37 : 0.81% | 31.32 : 0.82% | 31.27 : 0.83% | 31.22 : 0.84% | 31.16 : 0.85% |
31.11 : 0.86% | 31.06 : 0.87% | 31.01 : 0.88% | 30.96 : 0.89% | 30.91 : 0.90% |
30.86 : 0.91% | 30.81 : 0.92% | 30.76 : 0.93% | 30.71 : 0.94% | 30.66 : 0.95% |
30.61 : 0.96% | 30.56 : 0.97% | 30.51 : 0.98% | 30.46 : 0.99% | 30.41 : 1.00% |
30.36 : 1.01% | 30.31 : 1.02% | 30.26 : 1.03% | 30.21 : 1.04% | 30.16 : 1.05% |
30.11 : 1.06% | 30.07 : 1.07% | 30.02 : 1.08% | 29.97 : 1.09% | 29.92 : 1.10% |
29.87 : 1.11% | 29.82 : 1.12% | 29.78 : 1.13% | 29.73 : 1.14% | 29.68 : 1.15% |
29.63 : 1.16% | 29.58 : 1.17% | 29.54 : 1.18% | 29.49 : 1.19% | 29.44 : 1.20% |
29.40 : 1.21% | 29.35 : 1.22% | 29.30 : 1.23% | 29.25 : 1.24% | 29.21 : 1.25% |
29.16 : 1.26% | 29.11 : 1.27% | 29.07 : 1.28% | 29.02 : 1.29% | 28.98 : 1.30% |
28.93 : 1.31% | 28.88 : 1.32% | 28.84 : 1.33% | 28.79 : 1.34% | 28.75 : 1.35% |
28.70 : 1.36% | 28.66 : 1.37% | 28.61 : 1.38% | 28.57 : 1.39% | 28.52 : 1.40% |
28.48 : 1.41% | 28.43 : 1.42% | 28.39 : 1.43% | 28.34 : 1.44% | 28.30 : 1.45% |
28.25 : 1.46% | 28.21 : 1.47% | 28.16 : 1.48% | 28.12 : 1.49% | 28.08 : 1.50% |
28.03 : 1.51% | 27.99 : 1.52% | 27.94 : 1.53% | 27.90 : 1.54% | 27.86 : 1.55% |
27.81 : 1.56% | 27.77 : 1.57% | 27.73 : 1.58% | 27.68 : 1.59% | 27.64 : 1.60% |
27.60 : 1.61% | 27.56 : 1.62% | 27.51 : 1.63% | 27.47 : 1.64% | 27.43 : 1.65% |
27.38 : 1.66% | 27.34 : 1.67% | 27.30 : 1.68% | 27.26 : 1.69% | 27.22 : 1.70% |
27.17 : 1.71% | 27.13 : 1.72% | 27.09 : 1.73% | 27.05 : 1.74% | 27.01 : 1.75% |
26.97 : 1.76% | 26.92 : 1.77% | 26.88 : 1.78% | 26.84 : 1.79% | 26.80 : 1.80% |
26.76 : 1.81% | 26.72 : 1.82% | 26.68 : 1.83% | 26.64 : 1.84% | 26.60 : 1.85% |
26.56 : 1.86% | 26.52 : 1.87% | 26.48 : 1.88% | 26.44 : 1.89% | 26.40 : 1.90% |
26.36 : 1.91% | 26.32 : 1.92% | 26.28 : 1.93% | 26.24 : 1.94% | 26.20 : 1.95% |
26.16 : 1.96% | 26.12 : 1.97% | 26.08 : 1.98% | 26.04 : 1.99% | 26.00 : 2.00% |
25.96 : 2.01% | 25.92 : 2.02% | 25.88 : 2.03% | 25.84 : 2.04% | 25.80 : 2.05% |
25.76 : 2.06% | 25.73 : 2.07% | 25.69 : 2.08% | 25.65 : 2.09% | 25.61 : 2.10% |
25.57 : 2.11% | 25.53 : 2.12% | 25.50 : 2.13% | 25.46 : 2.14% | 25.42 : 2.15% |
25.38 : 2.16% | 25.34 : 2.17% | 25.31 : 2.18% | 25.27 : 2.19% | 25.23 : 2.20% |
25.19 : 2.21% | 25.16 : 2.22% | 25.12 : 2.23% | 25.08 : 2.24% | 25.05 : 2.25% |
25.01 : 2.26% | 24.97 : 2.27% | 24.94 : 2.28% | 24.90 : 2.29% | 24.86 : 2.30% |
24.83 : 2.31% | 24.79 : 2.32% | 24.75 : 2.33% | 24.72 : 2.34% | 24.68 : 2.35% |
24.64 : 2.36% | 24.61 : 2.37% | 24.57 : 2.38% | 24.54 : 2.39% | 24.50 : 2.40% |
24.46 : 2.41% | 24.43 : 2.42% | 24.39 : 2.43% | 24.36 : 2.44% | 24.32 : 2.45% |
24.29 : 2.46% | 24.25 : 2.47% | 24.22 : 2.48% | 24.18 : 2.49% | 24.15 : 2.50% |
24.11 : 2.51% | 24.08 : 2.52% | 24.04 : 2.53% | 24.01 : 2.54% | 23.97 : 2.55% |
23.94 : 2.56% | 23.90 : 2.57% | 23.87 : 2.58% | 23.83 : 2.59% | 23.80 : 2.60% |
23.76 : 2.61% | 23.73 : 2.62% | 23.70 : 2.63% | 23.66 : 2.64% | 23.63 : 2.65% |
23.59 : 2.66% | 23.56 : 2.67% | 23.53 : 2.68% | 23.49 : 2.69% | 23.46 : 2.70% |
23.43 : 2.71% | 23.39 : 2.72% | 23.36 : 2.73% | 23.33 : 2.74% | 23.29 : 2.75% |
23.26 : 2.76% | 23.23 : 2.77% | 23.19 : 2.78% | 23.16 : 2.79% | 23.13 : 2.80% |
23.10 : 2.81% | 23.06 : 2.82% | 23.03 : 2.83% | 23.00 : 2.84% | 22.97 : 2.85% |
22.93 : 2.86% | 22.90 : 2.87% | 22.87 : 2.88% | 22.84 : 2.89% | 22.80 : 2.90% |
22.77 : 2.91% | 22.74 : 2.92% | 22.71 : 2.93% | 22.68 : 2.94% | 22.64 : 2.95% |
22.61 : 2.96% | 22.58 : 2.97% | 22.55 : 2.98% | 22.52 : 2.99% | 22.49 : 3.00% |


2008/5/25 ruy de oliveira souza <ruymatrix@xxxxxxxxx>:
> Pretendo financiar um carro, supostamente  a juros mensais de 0,79% ao mês.
> Dizem que eles imbutem nas parcelas uma tal taxa de retorno(ilegal). alguém
> conhece a fórmula matemática para financiamentos desse tipo? Talvez não seja
> tão off topic se o financiamento for caracterizado pela taxa supracitada num
> período de 36 meses. Me perdoem por não ter colocado aqui um problema com as
> características da lista, mas me vejo apreensivo ante a expectativa de ser
> enganado. Agradeço a quem me apresentar a fórmula( algoritmo).
>
> 2008/5/15, Walter Tadeu Nogueira da Silveira <wtadeu10@xxxxxxxxx>:
>>
>> Obrigado mesmo Ralph
>>
>> Abraços
>>
>>
>

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