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1. No,it isn't
2.The medicine just stop the common cold for a little time and then the cold'll be back again
3.Because they can give use a lot of vitamin C and energy too.They'll help us to agaistthe virus
1) she has a lot of friends in her new school
2) Are you studying English at the moment ?
3) How far is it from your house to the market ?
4) I go to school by bus every day
5) How does your father go to work ?
1.She has a lot of friends in her new school
2. Are you stuying english at the moment?
3.how is it far from your house to the market?
4. i go to school by bus everyday
5. how does your go to work?
ban oi, day la trang hoc toan ma, ban ko nen hoi tieng anh . Nhung mk chi gop y thoi nhe, chuc ban hoc tot.
Lời giải:
Gọi số sách mà Clara đã mua là $a$ và số tạp chí đã mua là $b$ (\(a,b\in\mathbb{N}^*\) )
Theo bài ra ta có: \(3,4a+1,6b=23\)
\(\Rightarrow 3,4a=23-1,6b\leq 23-1,6.1\) do \(b\geq 1\)
hay \(3,4a\leq 21,4\Rightarrow a\leq \frac{21,4}{3,4}\Rightarrow a\leq 6\)
Vì \(a\in\mathbb{N}^*\Rightarrow a\in\left\{1;2;3;4;5;6\right\}\)
Nếu \(a=1\Rightarrow b=\frac{23-3,4}{1,6}=\frac{49}{4}\not\in\mathbb{N}^*\) (loại)
Nếu \(a=2\Rightarrow b=\frac{23-3,4.2}{1,6}=\frac{81}{8}\not\in\mathbb{N}^*\) (loại)
Nếu \(a=3\Rightarrow b=\frac{23-3,4.3}{1,6}=8\) (thỏa mãn)
Nếu \(a=4\Rightarrow b=\frac{23-3,4.4}{1,6}=\frac{47}{8}\not\in\mathbb{N}\) (loại)
Nếu \(a=5\Rightarrow b=\frac{23-3,4.5}{1,6}=\frac{15}{4}\not\in\mathbb{N}^*\) (loại)
Nếu \(a=6\Rightarrow b=\frac{23-3,4.6}{1,6}=\frac{13}{8}\not\in\mathbb{N}^*\) (loại )
Vậy Clara mua $3$ quyển sách và $8$ quyển tạp chí.
1. Tea can"t be made with cold water 2. Some of my book have been taken away 3. The meeting will be hold before... 4. The window was broken by the boys and some pictures were taken away