Question

(-0,3).1/10+5,4-13/20 ?

Answer 1

$\mathsf{(-0,3)\cdot\dfrac{1}{10}+5,4-\dfrac{13}{20}}\\\\\\\mathsf{Vamos\ transformar\ tudo\ em\ fra\c{c}\~ao,\ exceto\ a\ multiplica\c{c}\~ao:}\\\\\mathsf{-3\cdot\dfrac{1}{10}+\dfrac{54}{10}-\dfrac{13}{20}=}\\\\\\\mathsf{\dfrac{-3}{10}+\dfrac{54\cdot2-13}{20}=}\\\\\\\mathsf{\dfrac{-3}{10}+\dfrac{108-13}{20}=} \\\\\\\mathsf{\dfrac{-3}{10}+\dfrac{95}{20}=} \\\\\\\mathsf{\dfrac{-3\cdot2+95}{20}=} \\\\\\\mathsf{\dfrac{-6+95}{20}=} \\\\\\\boxed{\mathsf{\dfrac{89}{20}=4,45}}$

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