Tính a=67/43+106/79+52/79+19/43
Tính 67/43+106/79+52/79+19/43
\(\frac{67}{43}+\frac{106}{79}+\frac{52}{79}+\frac{19}{43}\)
\(=\left(\frac{67}{43}+\frac{19}{43}\right)+\left(\frac{106}{79}+\frac{52}{79}\right)\)
\(=2+2\)
\(=4\)
\(Ta\) \(có\)
\(\frac{67}{43}+\frac{106}{79}+\frac{52}{79}+\frac{19}{43}\)
\(=\left(\frac{67}{43}+\frac{19}{43}\right)+\left(\frac{106}{79}+\frac{52}{79}\right)\)
\(=\frac{86}{43}+\frac{158}{79}\)
\(=\frac{6794}{3397}+\frac{6794}{3397}\)
\(=\frac{13588}{10094}=\frac{6794}{5047}\)
A=67/43+106/79+52/79+19/43=?
nếu biết mình cảm ơn
mk ko ghi lại đề bài nha
A = ( 67/43 + 19/43 ) + (106/79 + 52/79)
A = 86/43 + 158/79
A = 2 + 2
A = 4
k mk nha bn
A = 67/43 + 106/79 + 52/79 + 19/43
A = ( 67/43 + 19/43 ) + ( 106/79 + 52/79 )
A = 2 + 2
A = 4 .
100 % LÀ ĐÚNG . CÂU NÀY THẦY GIÁO GIẠY MK NÈ.
NHỚ K CHO MIK NHÉ .
tìm số nguyên x,biết
a, 159 - ( 25 - x ) = 43
b,( 79 - x ) -43 = -( 17 - 52 )
a, 159 - ( 25 - x) = 43
159 - 25 + x = 43
134 + x = 43
x = 43 - 134
x = - 91
b, ( 79 -x) - 43 = -( 17 -52)
79 - x - 43 = -( -35)
36-x = 35
x = 36- 35
x = 1
a,159 - ( 25 - x ) = 43
25 - x = 159 - 43
25 - x = 116
x = 25 - 116
x = - 91
b, ( 79 - x ) - 43 = -( 17 - 52 )
( 79 - x ) - 43 = - 17 + 52
( 79 - x ) - 43 = 35
79 - x = 35 + 43
79 - x = 78
x = 79 - 78
x = 1
a) 159- (25-x)=43. (159-25)+x=43. 134+x=43. x=43-134. x=(-91). b) (79-x)-43=-(17-52). (79-x)-43=35. (79-43)-x=35. 36-x=35. x=36-35. x=1
Tìm số nguyên x , biết: a)159−(25−x)=43
b) (79−x)−43=−(17−52)
159 − (25 − x) = 43
159 − 25 + x = 43
x = 43 − 159 + 25
x = −91.
(79 − x) − 43 = −(17 − 52)
79 − x − 43 = −17 + 52
−x = −17 + 52 − 79 + 43
−x = −1
x = 1.
Bài 1: Tìm x nguyên, biết:
a) x + 5 = 20 - (12 -7)
b)15 - (3+ 2x) = 22
c) -11 - (19 - x) = 50
d)159 - (25 - x) = 43
e) (79 - x) - 43 = - (17 - 52)
f) (7 + x) - (21 - 13) = 32
g) - x + 20 = (-15) + 8 + 13
h) - (-x + 13 -142) + 18 = 55
Xin cảm ơn!
a) \(x+5=20-\left(12-7\right)\)
\(\Rightarrow x+5=20-5\)
\(\Rightarrow x+5=15\)
\(\Rightarrow x=15-5\)
\(\Rightarrow x=10\)
b) \(15-\left(3+2x\right)=2^2\)
\(\Rightarrow3+2x=15-4\)
\(\Rightarrow3+2x=11\)
\(\Rightarrow2x=11-3\)
\(\Rightarrow2x=8\)
\(\Rightarrow x=\dfrac{8}{2}\)
\(\Rightarrow x=4\)
c) \(-11-\left(19-x\right)=50\)
\(\Rightarrow19-x=-11-50\)
\(\Rightarrow19-x=-61\)
\(\Rightarrow x=61+19\)
\(\Rightarrow x=80\)
d) \(159-\left(25-x\right)=43\)
\(\Rightarrow25-x=159-43\)
\(\Rightarrow25-x=116\)
\(\Rightarrow x=25-116\)
\(\Rightarrow x=-91\)
e) \(\left(79-x\right)-43=-\left(17-52\right)\)
\(\Rightarrow\left(79-x\right)-43=52-17\)
\(\Rightarrow79-x-43=35\)
\(\Rightarrow36-x=35\)
\(\Rightarrow x=1\)
f) \(\left(7+x\right)-\left(21-13\right)=32\)
\(\Rightarrow7+x-8=32\)
\(\Rightarrow x-1=32\)
\(\Rightarrow x=32+1\)
\(\Rightarrow x=33\)
g) \(-x+20=-15+8+13\)
\(\Rightarrow-x+20=6\)
\(\Rightarrow x=20-6\)
\(\Rightarrow x=14\)
h) \(-\left(-x+13-142\right)+18=55\)
\(\Rightarrow x-13+142+18=55\)
\(\Rightarrow x+147=55\)
\(\Rightarrow x=55-147\)
\(\Rightarrow x=-92\)
Câu 1 : tính nhanh
a) ( -7) . 11 + 7 . ( - 89 )
b) ( -57) . ( 67 - 34) - 67 . ( 34 - 57 )
c) ( 17 - 25 ) - ( - 37 - 25 + 17 )
d) - ( -72 - 25 + 17 ) + ( - 72 + 17 )
e) ( -25 ) . ( -13) .8 (-4).125
f) 38 . (-43) + 43 . (-79) - (-43) . 17
e, (-25).(-13).8.(-4).125
= (-25).(-4).8.125.(-13)
= 100.1000.(-13)=-1300000
f, 38.(-43)+43.(-79)-(-43).17
= 38.(-43)+(-43).79-(-43).17
= (-43).(38+79-17)
= (-43).100=-4300
a) ( -7) . 11 + 7 . ( - 89 )
= 7 . (-11) + 7 . (-89)
= 7 . [(-11)+(-89)]
= 7 . (-100)
= -700
b, (-57).(67-34)-67.(34-57)
= -57.67+57.34-67.34+67.57
= 34(57-67)=34.(-10)=-340
c, (17-25)-(-37-25+17)
= 17-25+37+25-17
=37
d, -(-72-25+17)+(-72+17)
= 72+25-17-72+17= 25
Đặt tính rồi tính:
a) 19 315 + 43 627 b) 79 371 – 47 849
c) 4 132 x 23 d) 1 929 : 32
Bỏ ngoặc rồi tính:
f. (36 + 79) + (145 - 79 - 36)
g. 10 - [12 - (-9 - 1]
h. (38 - 29 + 43) - (43 + 38)
i. 271 - [(-43) + 271 - (-17)]
k. -144 - [29 - (+144) - (+144)]
f,(36+79)+(145-79-36)
=36+79+145-79-36
=(36-36)+(79-79)+145
=0+0+145
=145
g,10-[12-(-9-1)]
=10-(12+9+1)
=10-(12+10)
=10-12-10
=(10-10)-12
=0-12
=-12
h,(38-29+43)-(43+38)
=38-29+43-43-38
=(38-38)-29+(43-43)
=0-29+0
=-29
i,271-[(-43)+271-(-17)]
=271-(-43+271+17)
=271+43-271-17
=(271-271)+(43-17)
=0+26
=26
k,-144-[29-(+144)-(+144)]
=-144-(29-144-144)
=-144-29+144+144
=(-144+144)-29+144
=0-29+144
=-29+144
=115
Bỏ dấu ngoặc rồi tính
a ) 159 − 524 − 59 − 424 ; b ) 36 + 79 + 145 − 79 − 36 ; c ) 334 − 117 + 234 + 42 + 117 ; d ) 271 − − 43 + 271 − − 17 .
a ) 159 − 524 − 59 − 424 ; = 159 − 524 − 59 + 424 = 159 − 59 − 524 − 424 = 100 − 100 = 0 b ) 36 + 79 + 145 − 79 − 36 ; = 36 + 79 + 145 − 79 − 36 = 36 − 36 + 79 − 79 + 145 = 145 c ) 334 − 117 + 234 + 42 + 117 ; = 334 − 117 − 234 + 42 + 117 = 334 − 234 − 117 − 117 + 42 = 100 + 42 = 142 d ) 271 − − 43 + 271 − − 17 . = 271 − − 43 + 271 + 17 = 271 + 43 − 271 − 17 = 271 − 271 + 43 − 17 = 26