bài 1: tính
ví dụ: 25-2:(3/5-1/2)+(5/2+1/5x1/4)
=25-2:1/10+(5/2+1/20)
=25-20+51/20
=5+51/20=151/20
a, (3/10+4/5x1/2):(17/9-4/3:3) b, (6:3/5-7/6x3/14):(21/5x10/11+57/11)
c, 4x1/5+(1/5-1/7)x(1/2:1/7)
ai làm nhanh mình tik
bài 1: tính
ví dụ: 25-2:(3/5-1/2)+(5/2+1/5x1/4)
=25-2:1/10+(5/2+1/20)
=25-20+51/20
=5+51/20=151/20
a, (6:3/5-7/6x3/14):(21/5x10/11+57/11) b, 4x1/5+(1/5-1/7)x(1/2:1/7)
mình đang cần gấp. cảm ơn
bài 1: tính
ví dụ: 25-2:(3/5-1/2)+(5/2+1/5x1/4)
=25-2:1/10+(5/2+1/20)
=25-20+51/20
=5+51/20=151/20
a, (6:3/5-7/6x3/14):(21/5x10/11+57/11)
b, 4x1/5+(1/5-1/7)x(1/2:1/7)
mình đang cần gấp, mình sắp đi học rồi giúp tớ nhé
bài 1: tính
ví dụ: 25-2:(3/5-1/2)+(5/2+1/5x1/4)
=25-2:1/10+(5/2+1/20)
=25-20+51/20
=5+51/20=151/20
a, (3/10+4/5x1/2):(17/9-4/3:3) b, (6:3/5-7/6x3/14):(21/5x10/11+57/11)
c, 4x1/5+(1/5-1/7)x(1/2:1/7)
ai làm nhanh mình tik
bài 1: tính
mẫu: 25-2:(3/5-1/2)+(5/2+1/5x1/4)
=25-2:1/10+(5/2+1/20)
=25-20+51/20
=5+51/20=151/20
a, (6:3/5-7/6x3/14):(21/5x10/11+57/11) b, (6:3/5-7/6x3/14):(21/5x10/11+57/11)
mình đang cần gấp. giúp mình nhé
3:1/2=?
1/2:3=?
2.tính theo mẫu
a)9/10*5/6=9*5 10*6=3*3*5 5*2*3*2=3/4
b)6/25:21/20=
40/7*14/5=
17/13:51/26=
\(3\div\frac{1}{2}=3\times\frac{2}{1}=6\)
\(\frac{1}{2}\div3=\frac{1}{2}\times\frac{1}{3}=\frac{1}{6}\)
2.Tính theo mẫu :
b) \(\frac{6}{25}\div\frac{21}{20}=\frac{6}{25}\times\frac{20}{21}=\frac{6\times20}{25\times21}=\frac{2\times3\times4\times5}{5\times5\times3\times7}=\frac{8}{35}\)
\(\frac{40}{7}\times\frac{14}{5}=\frac{40\times14}{7\times5}=\frac{5\times8\times7\times2}{7\times5}=16\)
\(\frac{17}{13}\div\frac{51}{26}=\frac{17}{13}\times\frac{26}{51}=\frac{17\times13\times2}{13\times17\times3}=\frac{2}{3}\)
Chúc bạn hok tốt !
Bài 1:
\(3:\frac{1}{2}=3x2=6\)
\(\frac{1}{2}:3=\frac{1}{2}x\frac{1}{3}=\frac{1}{6}\)
Bài 2L
b) \(\frac{6}{25}:\frac{21}{20}=\frac{6}{25}\times\frac{20}{21}=\frac{2\times3\times4\times5}{5\times5\times3\times7}=\frac{8}{7}\)
\(\frac{40}{7}\times\frac{14}{5}=\frac{8\times5\times2\times7}{7\times5}=16\)
\(\frac{17}{13}:\frac{51}{26}=\frac{17}{13}\times\frac{26}{51}=\frac{17\times2\times13}{13\times17\times3}=\frac{2}{3}\)
Tính nhanh:A=1*5*6+2*10*12+3*15*18+4*20*24+5*25*30/1*3*5+2*6*10+3*9*15+4*12*20+5*15*25
ta có : (ghi lại đề)
=6+12+18+24+30/3+6+9+12+15
=2*(3/3+6/6+9/9+12/12+15/15)
=2*(1+1+1+1+1)
=2*5=10
chúc main học tốt nhé
1.Khoanh vào các phân số bằng nhau
a.1/2, 2/4, 5/8, 4/8, 9/10, 3/6
b.1/4, 2/9, 2/8, 3/12, 5/16, 5/20
c.2/5, 4/15, 8/20, 8/25, 10/25, 12/20
\(a,\dfrac{1}{2}=\dfrac{2}{4}=\dfrac{4}{8}=\dfrac{3}{6}\\ b,\dfrac{1}{4}=\dfrac{2}{8}=\dfrac{3}{12}=\dfrac{5}{20}\\ c,\dfrac{2}{5}=\dfrac{8}{20}=\dfrac{10}{25}\)
tính nhanh:
a) 1/2*2/3 ; 5/6*6/7 ; 10/15*15/20 ;24/25*25/36
b)1/2*2/3*3/4*4/5*5/6*6/7*7/8*8/9*9/10
b)1/2*2/3*3/4*4/5*5/6*6/7*7/8*8/9*9/10
=1x2x3x4x5x6x7x8x9
2x3x4x5x6x7x8x9x10
= 1
10
Tính nhanh(áp dụng tính chất của phép cộng)
126+(-20) +2004+(-106)
-5-4-3-2-1+1+2+3+4+5
1-2+3-4+5-6+7-8+9-10
-329+(15-101)-(25-440)
-357-(29-51)+(17-33)
4+(37-15)-(-32-15)
a: =126-20-106+2004=2004
b: =(-5+5)+(-4+4)+...+(-1+1)=0
d: =-329+15-101-25+440
=-10