Tinh bang cach thuan tien nhat:
a/ 7,8 x 34,5 + 15,5 x 7,8
b/ 3/7 x 11/5 + 4/7 x 11/5
tinh bang cach thuan tien 3/5 x 7/9 + 11/9 x 3/5 - 3/10. B 14/13 : 1/2 + 3/13 x2 -2 x 7/13
a) 3/5x7/9+11/9x3/5
=3/5 x(7/9+11/9)
= 3/5x2
=6/5
b)14/13:1/2+3/13x2-2x7/13
= 14/13 x 2 +3/13 x2 - 2x7/13
=2 x (14/13 +3/13 -7/13)
= 2 x 10/13
= 20/13
a) 3/5 x 7/9 + 11/9 x 3/5 - 3/10
= 3/5 x 7/9 + 11/9 x 3/5 - 3/5 x 2
= 3/5 x ( 7/9 + 11/9 - 2 )
= 3/5 x 0
= 0
b) 14/13 : 1/2 + 3/13 x 2 - 2 x 7/13
= 14/13 x 2/1 + 3/13 x 2 - 2 x 7/13
= ( 14/13 + 3/13 - 7/13 ) x 2
= 10/13 x 2 = 20/13
chẳng hiể gì cả
tinh bang cach thuan tien nhat : 3/4 x 4/5 + 5/6 x 6/7 x 7/8
giup minh
tinh bang cach thuan tien
3/7 x 5/6 + 4/7 x 5/6
3/7*5/6+4/7*5/6
= 5/6*(3/7+4/7)
=5/6*1
=5/6
Tinh bang cach thuan tien nhat:
a.20,13 x 84,5 x 20,13
b. 4,5 x 11/5 + 5,5 x 11/5
a. 20,13 x 84,5 x 20,13
= 20,13 x 84,5 x 20,13 x 1
= 20,13 x ( 84,5 + 1 )
= 20,13 x 85,55
b. 4,5 x 11/5 + 5,5 x 11/5
= ( 4,5 + 5,5 ) x 11/5
= 10 x 11/5
= 22
a]20,13 * 84,5 * 20,13 = 20,13 * 2 * 84,5
= 20,13 * 169
= 3401,97
b] 4,5 * 11/5 + 5,5 * 11/5 = 11/5 * [4,5 + 5,5]
= 2,2 * 10
= 22
giup minh
tinh bang cach thuan tien
7/9 x 5/16 : 5/9 x 4/7
7/9 x 5/16 : 5/9 x4/7
=7/9 x 5/16 x9/5 x 4/7
=7/9 x 45/80 x 4/7
=7/9 x 9/16 x 4/7
=7 x 9 x 4 /9 x 16 x 7
=1/4
tinh bang cach thuan tien
1.25 - 6.75 + 6.75 + 11 x 65 -1.25+33 x 5
=(1.25-1.25)-(6.75-6.75)+11x65+11x3x5
=0-0+11x(65-15)
=11x50
=550
1.25 - 6.75 + 6.75 + 11 x 65 -1.25+33 x 5
=(1.25-1.25)+(6.75-6.75)+11.65+11.3.5
=0+0+11.65+11.(3.5)
=11.65+11.15
=11.(65+15)
=11.80
=880
Bạn "Frisk" sai dấu nha,dòng 3
tinh bang cach thuan tien nhat 47 / 30 : 5/7 - 17/30 x 5/7
( 5 + 10 + 15 + 20 + 25 + 30 + 35 ) x ( 42 - 6 x 7 )
tinh bang cach thuan tien nhat
( 5 + 10 + 15 + 20 + 25 + 30 + 35 ) x ( 42 - 6 x 7 )
= ( 5 + 10 + 15 + 20 + 25 + 30 + 35 ) x ( 42 - 42 )
= ( 5 + 10 + 15 + 20 + 25 + 30 + 35 ) x 0
= 0
tinh bang cach thuan tien nhat
a(6/11 + 5/11)*3/7
b.3/5 * 7/9 +3/5*2/9
c.(6/7 - 4/7) : 2/5
d.(8/15 : 2/11 + 7/15 : 2/11