a: =4/15+21/15=25/15=5/3
b: =16/72+27/72=43/72
c: =48/20+15/20=63/20
a: =4/15+21/15=25/15=5/3
b: =16/72+27/72=43/72
c: =48/20+15/20=63/20
Bài 12. Tính a) 7/12 + 3/4 x 2/9 b) 8/9-4/15:2/5 c) (7/9+5/6)x3/5
a) 60 × (7/12 + 4/15) =
b) 5/6 ×( 6/5 - 6/7 ) =
c) 1/2 × 2/3 × 3/4 × 4/5 × 5/6× 6/7 × 7/8 × 8/9 =
a) 5/9 + 3/8 = ?
b) 8/12 - 1/3 = ?
c) 4/7 x 5/2 = ?
d) 5/11 : 15/22 = ?
Bài 3 : Tính
a) 11/7 + 3/5 , 4 + 1/9 b) 21/5 - 5/8 , 2 - 11/15
c) 3/19 x 38/9 , 21/5 x 2 c) 7/3 : 4/9 , 12/7 : 3
tinh
a 7/15 + (5/6 - 1/3) =
b 4/7 *21/16 : 5/8 =
c 15/8 - 4/9 * 6/8+ 1/6 =
d 5/12+(3/4 + 2/3 ) : 34/3 =
Bài 1:Tính
a) 11/4 - 9/8 + 15/12 b) 6/7 x 21/12 + 5/3
c) 13/18 : 5/9 -1 d) 3 + 9/4 : 3/5
tìm X biết :
a.2/3 : 5/7 : x/9 = 2/7 : 3/5 :10/9
b.3/5 : 7/x : 3/4 = 12/105
c.x : 1/2 = 2/3 x 4/5 x 3/4 x 15/8
a,6/7 - 5/7 + 4/7 - 3/7 + 2/7 - 1/7 ( B3: Tính = cách thuận tiện nhất )
b, 3/4- 3/5 + 1/4 - 2/5
B4 : so sánh 2 phân số [ >,<,= ]
a, 12/36...1/3 b, 5/4...6/7 c, 7/9...8/9
d,11/15...1/13 1/2...5/10
B5: Đặt tính rồi tính
a, 5/15 + 2/5 b, 2/7 + 12/21 c,16/24 + 5/12 d,1/3 + 1/4 + 5/6
d, 19/24 - 3/8 e,8/9 - 1/3 g,3+1/3 k, 5/8 + 7/4 + 7/12
Bài 9: Tính bằng cách thiện tiện nhất
A) 3/7 + 4/9 + 4/7 + 5/9 B) 1/5 + 4/11 + 4/5 + 7/11 C) 1/15 + 4/15 + 5/18 + 7/18 D) 1/8 + 1/12 + 3/8 + 5/12
~ GIÚP MÌNH VỚI MN ƠI ~