\(41,54-4,18+23,17+8,46-5,82-3,17\)

\(=\left(41,54+8,46\right)-\left(4,18+5,82\right)-\left(23,17-3,17\right)\)

\(=50-10-10\)

\(=30\)

\(0,24\times450+0,8\times15\times3+3\times4\times8\)

\(=0,24\times100\times4,5+0,8\times3\times15+3\times8\times4\)

\(=24\times4,5+2,4\times10\times1,5+24\times4\)

\(=24\times4,5+24\times1,5+24\times4\)

\(=24\times\left(4,5+1,5+4\right)\)

\(=24\times10\)

\(=240\)

\(>;< ;=?\)

\(192,4\times2\times4,7...384,8\times4,6\)

Ta có :

\(192,4\times2\times4,7=1808,56\)

\(384,8\times4,6=1770,08\)

Vì \(1808>1770\) nên \(1808,56>1770,08\) hay

\(\Rightarrow192,4\times2\times4,7>384,8\times4,6\)

Vậy ​\(192,4\times2\times4,7>384,8\times4,6\)

​

Hello ní

mik nhớ là bạn đã đăng cái này bên 247 r mà?

Khí CO2 ( carbon dioxide) ạ.

Chiều cao tam giác đó là:

\(26,4\times\dfrac{1}{2}=13,2\left(cm\right)\)

Diện tích tam giác đó là:

\(\dfrac{26,4\times13,2}{2}=174,24\left(cm^2\right)\)

Đáp số : \(174,24cm^2\)

\(a,\dfrac{6}{4}+\dfrac{6}{28}+\dfrac{6}{70}+\dfrac{6}{130}+\dfrac{6}{208}\)

\(=\dfrac{6}{1.4}+\dfrac{6}{4.7}+\dfrac{6}{7.10}+\dfrac{6}{10.13}+\dfrac{6}{13.16}\)

\(=2.\left(\dfrac{1}{1.4}+\dfrac{1}{4.7}+\dfrac{1}{7.10}+\dfrac{1}{10.13}+\dfrac{1}{13.16}\right)\)

\(=2.\left(1-\dfrac{1}{4}+\dfrac{1}{4}-\dfrac{1}{7}+\dfrac{1}{7}-\dfrac{1}{10}+\dfrac{1}{10}-\dfrac{1}{13}+\dfrac{1}{13}-\dfrac{1}{16}\right)\)

\(=2.\left(1-\dfrac{1}{16}\right)\)

\(=2.\dfrac{15}{16}=\dfrac{15}{8}=1,875\)

\(b,0,7\times430\times2+1,4\times570+200\)

\(=1,4\times430+1,4\times570+200\)
\(=1,4\times\left(430+570\right)+200\)

\(=1,4\times1000+200\)

\(=1400+200=1600\)

1 đúp (Đ)

2 đúp (S)

\(x\times\dfrac{9}{10}+x:10=1\)

\(x\times\dfrac{9}{10}+x\times\dfrac{1}{10}=1\)

\(x\times\left(\dfrac{9}{10}+\dfrac{1}{10}\right)=1\)

\(x\times1=1\)

\(x=1:1\)

\(x=1\)