X * 9 - (3 * X + 28) = 176
Tính bằng cách thuận tiện :
12/23 x 9/28 + 11/23 x 9/28 3 + 1/9 + 3/9 + 2 + 5/9 + 3 + 2
Bài 1 : Tính nhanh :
a, 2/3 + 3/4 + 4/5 + 12/9 + 28/6 + 48/15.
b, 3/5 + 4/7 + 2/8 + 10/25 + 9/21 + 28/16 ;
c , 8/7 + 7/6 + 5/8 + 10/12 + 24/28 + 6/16 ;
d, ( 1 + 1/2 ) x ( 1 + 1/3) x ( 1 + 1/4 ) x...x ( 1 + 1/175)
Tính :
100 x 96 =
300 x 28 =
336 x 76 =
( 9 x 325 ) - 6 : 3 =
4/7 + 2/8 =
8/6 - 8/24 =
9/28 x 14/9 =
7/6 : 2/3 =
b1
13956-8768 4368:78
4512:96 1665:45
b2
x:28-5:x=25
7/5 - 2/3 : x=1/10
b3
4/5*7 + 4/7*9 + 4/9*11 +.........+4/53*35
bài1; tính
a,5/7 ; 45 /28=
b,3/8 x 4/9 : 3=
bài2;
a,60 x ( 7/12 + 4/15 )
b,1/2 x2/3 x3/4 x 4/5 x 5/6 x 6/7 x 7/8 x 8/9
Bài 1: Tìm x
a, x + 15/16 + 7/8 = 15/4 b, x - 27/28 - 9/14 = 13/7
c, x nhân 1/5 + x + 1/6 = 2/3 d, x: 14 = 1/4 + 2/9 + 3/4