Question

1. Tính
a. 6/7 + 5/7 =
b. 4/9 - 1/6 =
c. 3/10 x 4/9 =
d. 3 : 1/2 =

Answer 1

\(a,\dfrac{6}{7}+\dfrac{5}{7}=\dfrac{12}{7}\)

\(b,\dfrac{4}{9}-\dfrac{1}{6}=\dfrac{24}{54}-\dfrac{9}{54}=\dfrac{15}{54}=\dfrac{5}{18}\)

\(c,\dfrac{3}{10}\times\dfrac{4}{9}=\dfrac{12}{90}=\dfrac{2}{15}\)

\(d,3:\dfrac{1}{2}=3\times2=6\)

Answer 2

Lời giải:

a.

$\frac{6}{7}+\frac{5}{7}=\frac{11}{7}$

b.

$\frac{4}{9}-\frac{1}{6}=\frac{8}{18}-\frac{3}{18}=\frac{5}{18}$

c.

$\frac{3}{10}\times \frac{4}{9}=\rac{12}{90}=\frac{12:6}{90:6}=\frac{2}{15}$

d.

$3: \frac{1}{2}=3\times 2=6$

Answer 3

\(a,\dfrac{6}{7}+\dfrac{5}{7}=\dfrac{6+5}{7}=\dfrac{11}{7}\)

\(b,\dfrac{4}{9}-\dfrac{1}{6}=\dfrac{8}{18}-\dfrac{3}{18}=\dfrac{8-3}{18}=\dfrac{5}{18}\)

\(c,\dfrac{3}{10}\times\dfrac{4}{9}=\dfrac{3\times4}{10\times9}=\dfrac{12}{90}=\dfrac{2}{15}\)

\(d,3:\dfrac{1}{2}=3\times\dfrac{2}{1}=\dfrac{6}{1}=6\)

Answer 4

Answer 5

b,49−16=2454−954=1554=518b,49−16=2454−954=1554=518

d,3:12=3×2=6 

Answer 6

6