160x5-25x4) :7-3*x=36*25:9-60
160x5-25x4) :7-3xX=36x25:9-60
Lời giải:
$(160\times 5-25\times 4):7-3\times x=36\times 25:9-60$
$(800-100):7-3\times x=(36:9)\times 25-60$
$700:7-3\times x=4\times 25-60$
$100-3\times x=100-60$
$100-3\times x=40$
$3\times x=100-40=60$
$x=60:3=20$
(160×5−25×4):7−3×x=36×25:9−60(160×5−25×4):7−3×�=36×25:9−60
(800−100):7−3×x=(36:9)×25−60(800−100):7−3×�=(36:9)×25−60
700:7−3×x=4×25−60700:7−3×�=4×25−60
100−3×x=100−60100−3×�=100−60
100−3×x=40100−3×�=40
3×x=100−40=603×�=100−40=60
x=60:3=20
(160x5-25x4):7-3xX=36x25:9-60
(160*5-25*4):7-3xX=40
97xX=40
X=97:40
X=2.245
mong bạn đánh giá kq của mình ^^
( 160 \(\times\) 5 - 25 \(\times\) 4 ) \(\div\) 7 - 3 \(\times\) \(x\) = 36 \(\times\) 25 \(\div\) 9 - 60
( 800 -100) \(\div\) 7 - 3 \(\times\) \(x\) = 900 \(\div\) 9 - 60
700 \(\div\) 7 - 3 \(\times\) \(x\) = 100 -60
100 - 3 \(\times\) \(x\) = 40
3 \(\times\) \(x\) = 100 - 40
3 \(\times\) \(x\) = 60
\(x\) = 60 \(\div\) 3
\(x\) = 20
tính:
a).12054:(15+67)
29150-136X201
B).9700:100+36X12
(160X5-25X4):4
LÀM ĐẦY ĐỦ TICK NHẺ
AI GIÚP LEJ
a.
12054: ( 15 + 67 )
= 12054 : 82
= 147
29150-136x201
=29150-27336
=1814
b) 9700:100+36x12
=97+432
=529
(160x5-25x4):4
=(800-100):4
= 700:4
=175
k mink nhé
A)1/10+4/20+9/30+25/50+36/60+49/70+64/80+81/90
B)2/3*5+2/5*7+2/7*9+...2/41*43
\(B=\frac{2}{3.5}+\frac{2}{5.7}+\frac{2}{7.9}+...+\frac{2}{41.43}\)
\(=\frac{1}{3}-\frac{1}{5}+\frac{1}{5}-\frac{1}{7}+\frac{1}{7}-\frac{1}{9}+...+\frac{1}{41}-\frac{1}{43}\)
\(=\frac{1}{3}-\frac{1}{43}\)
\(=\frac{40}{129}\)
p/s: chúc bạn học tốt
chứng minh B = 36 / 1 x 3 x 5 + 36 / 3 x 5 x7 + 36 / 5 x 7 x 9 + .... + 36 / 25 x 27 x29 < 3
\(B=\frac{36}{1.3.5}+\frac{36}{3.5.7}+\frac{36}{5.7.9}+...+\frac{36}{25.27.29}\)
\(=9.\left(\frac{4}{1.3.5}+\frac{4}{3.5.7}+\frac{4}{5.7.9}+...+\frac{4}{25.27.29}\right)\)
\(=9.\left(\frac{1}{1.3}-\frac{1}{3.5}+\frac{1}{3.5}-\frac{1}{5.7}+\frac{1}{5.7}-\frac{1}{7.9}+...+\frac{1}{25.27}-\frac{1}{27.29}\right)\)
\(=9.\left(\frac{1}{3}-\frac{1}{675}\right)\)
\(=9.\frac{224}{675}\)
\(=\frac{224}{75}\)
THIẾU
\(=\frac{224}{75}< \frac{225}{75}=3\)
Vậy \(B< 3\)
mấy bọn nguuuuuuuuuuuuuuuuuu
36/(1*3*5) + 36/(3*5*7) + 36/(5*7*9) + ... + 36/(25*27*29)
1. -2/9 x 15/17 + -2/9 x 2/17
2. -5/3 x 6/5 + -7/9 x 3/10
3. 15/20 x 7/5 + -9/7 x -6/4
4.-25/13 x 5/19 + -25/13 x 14/19
5 -7/13 x 13/5 + -9/7 x 5/3
6. 27/35 x 5/9 - 2/7 x -7/5
7. 10/13 x 13/5 + {-9/5} x 10/3
8. 100/27 x 9/20 + 40% x 5/3
9. 1,5 x 5/12 + 1/4 x 3/4
10. 2 1/2 x 7/5 + {-9/10} x 2/3
11. X + 45% = 2 1/2 -5/3
12. 80% + X = -5/2 + 3/4
13. 4/25 - X =-5/2 + -3/10
1: =-2/9(15/17+2/17)=-2/9
2: \(=\dfrac{-6}{3}+\dfrac{-21}{90}\)
=-2-7/30=-67/30
3: \(=\dfrac{3}{4}\cdot\dfrac{7}{5}+\dfrac{9}{7}\cdot\dfrac{3}{2}\)
=21/20+27/14=417/140
4: =-25/13(5/19+14/19)=-25/13
5: =-7/5-45/21=-7/5-15/7=-124/35
1: =-2/9(15/17+2/17)=-2/9
2: =34⋅75+97⋅32=34⋅75+97⋅32
=21/20+27/14=417/140
4: =-25/13(5/19+14/19)=-25/13
5: =-7/5-45/21=-7/5-15/7=-124/35
Tính rồi viết kết quả dưới dạng số thập phân:
a) 1/10 + 4/20 + 9/30 + 16/40 + 25/50 + 36/60 + 49/70 + 64/80 + 81/90
b: ( 4/5 x 3/8 + 4/5 x 5/8 - 4/5 x 7/8 ) : 1/2
a;
c; \(\dfrac{1}{10}\) + \(\dfrac{4}{20}\) + \(\dfrac{9}{30}\)+\(\dfrac{16}{40}+\dfrac{25}{50}+\dfrac{36}{60}+\dfrac{49}{70}+\dfrac{64}{80}+\dfrac{81}{90}\)
= \(\dfrac{1}{10}+\dfrac{2}{10}+\dfrac{3}{10}+\dfrac{4}{10}+\dfrac{5}{10}+\dfrac{6}{10}+\dfrac{7}{10}+\dfrac{8}{10}+\dfrac{9}{10}\)
= \(\dfrac{1+2+3+4+5+6+7+8+9}{10}\)
= \(\dfrac{\left(1+9\right)+\left(2+8\right)+\left(3+7\right)+\left(4+6\right)+5}{10}\)
= \(\dfrac{10+10+10+10+5}{10}\)
= \(\dfrac{\left(10+10+10+10\right)+5}{10}\)
= \(\dfrac{10\times4+5}{10}\)
= \(\dfrac{45}{10}\)
= \(\dfrac{9}{2}\)
CTR:36/1*3*5+36/3*5*7+36/5*7*9+...+36/25*27*29<3