a: (-14)+(-16)+24

=-14-16+24

=-30+24

=-6

b: |-25|x71+29x25

\(=25\cdot71+25\cdot29\)

\(=25\left(71+29\right)=25\cdot100=2500\)

c: \(=132:\left(41+28-5^2\right)\)

\(=132:\left(69-25\right)=132:44=3\)

Đáp án:

 a, 38+41+117+159+6238+41+117+159+62

=(38+62)+(41+159)+117=(38+62)+(41+159)+117

=100     +200      +117=100     +200      +117

=417=417

b, 73+86+968+914+303273+86+968+914+3032

=73+(86+914)+(968+3032)=73+(86+914)+(968+3032)

=73+1000     +4000=73+1000     +4000

=5073=5073

c, 341.67+341.16+659.83341.67+341.16+659.83

=341.(67+16)+659.83=341.(67+16)+659.83

=341.83+659.83=341.83+659.83

=83.(341+659)=83.(341+659)

=83.1000=83000=83.1000=83000

d, 42.53+47.156−47.11442.53+47.156-47.114

=42.53+47.(156−114)=42.53+47.(156-114)

=42.53 +47.42=42.53 +47.42

=42.(53+47)=42.100=42.(53+47)=42.100

=4200=4200

e, 563.23+23.26+23563.23+23.26+23

=23.(563+26+1)=23.(563+26+1)

=23.600=23.600

=13800=13800

f, 132+157+43+68132+157+43+68

=(132+68)+(157+43)=(132+68)+(157+43)

=200      +200=400=200      +200=400

g, 49.68+100.34+6849.68+100.34+68

=49.68+50.68+68=49.68+50.68+68

=68.(49+50+1)=68.(49+50+1)

=68.100=6800=68.100=6800

h, 491.(267+53)+491.(151+67)491.(267+53)+491.(151+67)

=491.(267+53+151+67)=491.(267+53+151+67)

=491.538=491.538

=264158=264158

Vote mk nha.

bằng 1/3 bạn nhé ..check mk đó.

\(\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\left(\frac{79}{67}-\frac{28}{41}\right)\)

\(=\frac{1}{3}+\frac{12}{67}+\frac{13}{41}-\frac{79}{67}+\frac{28}{41}\)

\(=\left(\frac{12}{67}-\frac{79}{67}\right)+\left(\frac{13}{41}+\frac{28}{41}\right)+\frac{1}{3}\)

\(=\left(-1\right)+1+\frac{1}{3}\)

\(=\frac{1}{3}\)

bằng \(\frac{1}{3}\)nhé

\(\left(\dfrac{1}{3}+\dfrac{12}{67}+\dfrac{13}{41}\right)-\left(\dfrac{79}{67}-\dfrac{28}{41}\right)\\ =\left(\dfrac{103}{201}+\dfrac{13}{41}\right)-\dfrac{1363}{2747}\\ =\dfrac{6836}{8241}-\dfrac{1363}{2747}\\ =\dfrac{1}{3}\)

\(\left(\dfrac{1}{3}+\dfrac{12}{67}+\dfrac{13}{41}\right)-\left(\dfrac{79}{67}-\dfrac{28}{41}\right)\\ =\dfrac{1}{3}+\dfrac{12}{67}+\dfrac{13}{41}-\dfrac{79}{67}+\dfrac{28}{41}\\ =\dfrac{1}{3}+\left(\dfrac{12}{67}-\dfrac{79}{67}\right)+\left(\dfrac{13}{41}+\dfrac{28}{41}\right)\\ =\dfrac{1}{3}-\dfrac{67}{67}+\dfrac{41}{41}\\ =\dfrac{1}{3}-1+1\\ =\dfrac{1}{3}\)

\(\left(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}\right)-\left(\frac{79}{67}-\frac{28}{41}\right)\)

=\(\frac{1}{3}+\frac{12}{67}+\frac{13}{41}-\frac{79}{67}+\frac{28}{41}\)

\(=\frac{1}{3}+\left(\frac{12}{67}-\frac{79}{67}\right)+\left(\frac{13}{41}+\frac{28}{41}\right)\)

\(=\frac{1}{3}-1+1\)

\(=\frac{1}{3}\)

(1/3+12/67+13/41)-(79/67-28/41).    =1/3+12/613/41-79/67+28/41.        =1/3+(12/67-79/67)+(13/41+28/41) =1/3+(-1)+1=1/3+0.   =1/3

cái nịt

2/15-2/65-4/39=4/39-4/39=0

32/13-(7/23+8/23)=32/13-15/23=541/299

(1/3+12/67+13/41) - (79/67 - 28/41)=6836/8241-1363/2747=1/3

38/145 - (8/45-17/51-3/11)=38/145-(-212/495)=1982/2871

\(\left(\dfrac{1}{3}+\dfrac{12}{67}+\dfrac{13}{41}\right)-\left(\dfrac{79}{67}-\dfrac{28}{41}\right)\)
\(=\dfrac{1}{3}+\dfrac{12}{67}+\dfrac{13}{41}-\dfrac{79}{67}+\dfrac{28}{41}\)
\(=\dfrac{1}{3}+\left(\dfrac{12}{67}-\dfrac{79}{67}\right)+\left(\dfrac{13}{41}+\dfrac{28}{41}\right)\)
\(=\dfrac{1}{3}+\left(-1\right)+1=\dfrac{1}{3}+0=\dfrac{1}{3}\)
\(\left(\dfrac{15}{4}-5x\right).\left(9x^2-4\right)=0\)
\(\left[{}\begin{matrix}\dfrac{15}{4}-5x=0\\9x^2-4=0\end{matrix}\right.\)
\(\left[{}\begin{matrix}5x=\dfrac{15}{4}\\9x^2=4\end{matrix}\right.\)
\(\left[{}\begin{matrix}x=\dfrac{3}{4}\\x=\dfrac{2}{3}\end{matrix}\right.\)