Bộ 30 Đề thi Toán học kì 2 lớp 4 có đáp án( đề 27)

Chọn đáp án là B

Chọn đáp án là A

$\begin{array}{l}a)456dm=0,0456km\\ b)342m^2=3420000c{m}^2\end{array}$

$c)2345m=2345000mm$

$d)456k{m}^2=456000000m^2$

$e)4dam=400dm$

$f)4000m^2=400000d{m}^2$

$\begin{array}{l}a)\frac{1}{2}+\frac{52}{4}=\frac{2}{4}+\frac{52}{4}=\frac{54}{4}=\frac{27}{2}\\ b)\frac{56}{5}:4=\frac{56}{5}\times \frac{1}{4}=\frac{14\times 1}{5\times 1}=\frac{14}{5}\\ c)\frac{12}{56}+\frac{7}{8}=\frac{12}{56}+\frac{49}{56}=\frac{61}{56}\\ d)\frac{25}{12}\times \frac{4}{5}=\frac{5\times 1}{3\times 1}=\frac{5}{3}\end{array}$

$a)234+376289=376523 ; b)2431-271=2160$

$c)467\times 216=100872\text{\hspace{0.17em} ; \hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}\hspace{0.17em}}d)23589:787=29$

$\begin{array}{l}a)x+\left(5621+1236\right)\times 5=225690\\ x+6857\times 5=225690\\ x+34285=225690\\ x=225690-34285=191405\end{array}$$\begin{array}{l}b)x-12\times 5\times 9+567=1000\\ x-540+567=1000\\ x=1000+540-567\\ x=973\end{array}$

$\begin{array}{l}c)x+2+x+4+x+6+x+8=25760\\ (x+x+x+x)+(2+4+6+8)=25760\\ 4x+20=25760\\ 4x=25760-20\\ 4x=25740\\ x=25740:4=6435\end{array}$$\begin{array}{l}d)\left(6975-x+785\right):4=859\\ 7760-x=859\times 4\\ 7760-x=3436\\ x=7760-3436=4324\end{array}$