Câu 4: trang 162 - toán tiếng Anh 5
Calculate using two methods:
Tính bằng hai cách:
a) $\frac{7}{11}:\frac{3}{5}+\frac{4}{11}:\frac{3}{5}$
b) (6,24 + 1,26) : 0,75
Bài Làm:
a) The 1st way:
$\frac{7}{11}:\frac{3}{5}+\frac{4}{11}:\frac{3}{5}$
$= \frac{7}{11}\times \frac{5}{3} + \frac{4}{11}\times \frac{5}{3} $
$= \frac{7\times 5}{11\times 3} + \frac{4\times 5}{11\times 3}$
$=\frac{35}{33}+\frac{20}{33}=\frac{55}{33}=\frac{5}{3}$
The 2nd way:
$\frac{7}{11}:\frac{3}{5}+\frac{4}{11}:\frac{3}{5}$
= $(\frac{7}{11} + \frac{4}{11}):\frac{3}{5}$
= $(\frac{7}{11} + \frac{4}{11}) \times \frac{5}{3}$
= $\frac{11}{11} \times \frac{5}{3}$ = $1 \times \frac{5}{3}$ = $\frac{5}{3}$
b) The 1st way:
(6,24 + 1,26) : 0,75 = 7,5 : 0,75 = 10
The 2nd way:
(6,24 + 1,26) : 0,75 = 6,24 : 0,75 + 1,62 : 0,75 = 8,32 + 1,68 = 10