1. 143/154 = 13/14
2. a) 7/6 > 3/9
b) 4/15 < 4/9 < 7/12
c) 1/12 < 5/6 < 9/8
duyệt đi
1.\(\frac{143}{154}=\frac{13}{13}\)
2. \(\frac{7}{6}>\frac{3}{9}\)
\(\frac{4}{15}<\frac{4}{9}<\frac{7}{12}\)
\(\frac{1}{12}<\frac{5}{6}<\frac{9}{8}\)
1.143/154 chia het cho cac so tu nhien lon hon 1 la:11
Vay ta rut gon 143/154 chia cho 11 vi 11 la so duy nhat tu so va mau so chia het cho so tu nhien lon hon 1.Ta rut gon 143/154=13/14
Dap so:13/14
2.a)
Ta thay 2 phan so mau so chung la 18 len ta duoc cach lam nhu sau:
Ta thay:18:6=3;18:9=2
Ta co:7/6=7x3/6x3=21/18; 3/9=3x2/9x2 = 6/18; 21/18>6/18 nen 7/6>3/9
b)
Ta thay 2 phan 4/9 va 4/15 co tu so giong nhau va phan so 7/12 khong co tu so giong voi 2 phan so kia len ta so sanh 2 tu so dau truoc
Nho lai:Muon so sanh hai phan cung tu so,ta so sanh phan so nao co mau so be hon thi lon hon
Ta co:4/9 va 4/15;9<15 nen 4/9>4/15
Ta sap sep:4/15<4/9<7/12
c)
Ta thay 3 phan so co mau so chung la 24 nen ta co cach lam nhu sau:
Ta thay:24:6=4 ;24:8=3 ;24:12=2
Ta co:5/6=20/24 ;9/8=27/24 ;1/12=2/24.Vi:20/24<27/24>2/24 nen 5/6<9/8>1/2
