Question

Cem Bombons Custam R$ 39,00.Entao,Quanto custam 310 Bombons e 79 Bombons

Answer 1

Uma regra de 3 simples resolve isso.
100 bombons = 39 reais
310 bombons = x
$100x = 310.39 \\ \\ x = \frac{12090}{100} = 120,9$

R: 310 bombons custam 120 reais e 90 centavos.
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100 bombons = 39 reais
79 bombons = x
$100x = 39.79 \\ \\ x = \frac{3081}{100} = 30,81$

R: 79 bombons custam 30 reais e 81 centavos.