7/10 + 5/9 + 13/10 +22/9
= [7/10 + 13/10 ] + [5/9+22/9]
=20/10 + 27/9
= 2+3=5
7/10 + 5/9 + 13/10 +22/9
= [7/10 + 13/10 ] + [5/9+22/9]
=20/10 + 27/9
= 2+3=5
bài 1: Tính bằng cách thuận tiện nhất
1+4+7+10+13+16+19+22+25+28
bài2:Tìm y:
a)y+253=1420 b)y-2316=902
bài3:Tính:
2754:9= 5089:7= 3675:5= 2010:6=
2754x9= 5089x7= 3675x5= 2010x 6=
>,<,=
a,2/3+3/4+4/5+7/9+9/11...................5
b,1/10+1/11+1/12+1/13+1/14...............1/5
c,15/5+13/11+22/21..................5
2/3 + 3/4
9/4 + 3/5
5/24 + 1/4
3/15 - 5/35 18/27 - 2/6 37/12 - 3
11/9 x 3/22 7/13 x 13/7 4 x6/7
2/5 : 3/10 3/8 : 9/4 8/21 : 4/7
Tính nhanh :
3/4 x 4/9 x 9/11 x 22/25 x 5/7 : 10/7
Bài 4: Tính bằng cách thuận tiện
a) 5/9 + 13/7 + 15/13 + 8/7 + 4/9 + 11/13
b) 3/5 + 18/9 + 4/10
a/9/22*33/18
b/12/35:36/25
c/19/17:76/51
Tính(theo mẫu)
Mẫu: 9/10*5/6=9*5/10*6=3*3*5/5*2*3*2=3/4
tính nhanh
a) \(\dfrac{4}{9}\) x \(\dfrac{3}{5}\) + \(\dfrac{4}{9}\) x \(\dfrac{8}{5}\) - \(\dfrac{4}{9}\) x \(\dfrac{2}{10}\)
b) 312 : 13 + 325 : 13 - 247 : 13
( ghi chi tiết giúp mk ạ )
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26=
Tính 1/2+3/6+5/10+7/14+9/18+11/22