Question

CÁLCULO MENTAL Calcule mentalmente e escreva o resultado. 3 5 a) de 8 = de 21 4 7 = b) 2 3 - de 6 d) de 20 = c/w​

Answer 1

a)

$\frac{3}{4} \times 8 = \frac{3 \times 8}{4} = \frac{24}{4} = 6$

b)

$\frac{2}{3} \times 6 = \frac{2 \times 6}{3} = \frac{12}{3} = 4$

c)

$\frac{5}{7} \times 21 = \frac{5 \times 21}{7} = \frac{105}{7} = 15$

d)

$\frac{3}{5} \times 20 = \frac{3 \times 20 }{5} = \frac{60}{5} = 12$