(x+1,750):0,12=1+2-3+4-5+6...+118-119+120
Tìm x :
(x + 1,75) : 0,12 = 1+2-3+4-5+6- ...+118-119+120
Tìm x
a) [(3.x-3/5):0,75].1/2/3+1/3=1
b) 1999.2001-1/1998+1999.2000 . 7/5.x=1
c) 11,13 + 13,15 + 15,17 + ... +31,33 = 5.x+11,13
d) (x+1,75):0,12=1+2-3+4-5+6- ... +118-119+120
e) (2/11.13 + 2/13.15 + ... + 2/19.21 ) . 462 - [2,04 : ( x + 1,05 ) ] : 0,12 = 11,5
So sanh A va B biet A=1×3×5×7ו••×9997×9999 va B=2×4×6ו••×9998×10000
So sanh A va B biet A=1×3×5×7ו••×9997×9999 va B=2×4×6ו••×9998×10000
So sanh A va B biet A =1×3×5×7ו••×9997×9999 va B=2×4×6ו••×9998×1000
so sanh hai phan so
1919/2121.........191919/212121
5/8cong1/8........3/4
1/42...................1/6-1/7
18/51.......................3/10
7/8-1/8...................5/6-1/3
( 3/10/99 + 4/11/119 - 5/8/299 ) * ( 1/2 -1/3 -1/6 ) =?
1 a, 3 va 1/5 - 2 va 1/6 + 1/5
b, 5 va 12/13 - 2 va 15/26 + 1/26
c, 7 va 1/12 + 1/12 - 6 va 1/4
2 tinh gia tri bieu thuc
a, 3 va 2/9 - [1 va 5/8 + 1 va 2/9 ] - 3/8
b, 4 va 2/5 - 1 va 3/7 - 1 va 4/7 + 1/5
c, 1 va 9/12 - 5/4 - 1/2
3 tinh
a, 6 nhan 7 nhan 8 nhan 9 nhan 1 tren 18 nhan 16 nhan 14 nhan 12 nhan 2
b, 4 nhan 15 nhan 9 nhan 24 tren 3 nhan 12 nhan 8 nhan 5
4 rut gon cac phan so
a, 96/150 ; 255/408 ; 630/224
b, 1515/1717; 352352/470470; 200620062006/200520052005
5 so sanh cac phan so
a, 7/9 va 9/7 ; b, 135/120 va 13/8; c, 3535/4848 va 5/8 ; d, 650650/480480 va 222222/144144
6, so sanh hai phan so
a, 2005/2006 va 2006/2007 ; b, 2008/2007 va 2007/2006
cac ban lam tung buoc nha