Question

se A=2/3•1/4 e B=1/2.3/5 Então o valor de A + B é:

a) 7/15
b) 7/20
c) 8/60​
d)18/60

Answer 1

Resposta:

$a + b = \frac{7}{15} \\ \\ a) \: \: \: \frac{7}{15}$

Explicação passo-a-passo:

$a = \frac{2}{3} \times \frac{1}{4} = \frac{2 \times 1}{3 \times 4} = \frac{2}{12} = \frac{2 \div 2}{12 \div 2} = \frac{1}{6} \\ a = \frac{1}{6} \\ \\ b = \frac{1}{2} \times \frac{3}{5} = \frac{1 \times 3}{2 \times 5} = \frac{3}{10} \\ b = \frac{3}{10} \\ \\ a + b \\ \frac{1}{6} + \frac{3}{10} = \frac{5 + 9}{30} = \frac{14}{30} = \frac{14 \div 2}{30 \div 2} = \frac{7}{15} \\ \\ a + b = \frac{7}{15}$