Cac phan so
5 / 9 ; 15 / 45 ; 3 / 7 ; 11 / 19 ; 16 / 31
phan so nao bang phan so 1 / 3
cho phan so 31/32. Hay tim tong tat ca cac phan so bang phan số 31/32 ma co tu so cua moi phan so bang 1
Tinh nhanh :
a . 1/4 + 2/5 + 6/8 + 9/15 + 8/1
b . 15/31 * 16/43 + 15/31 * 27 4
Quy dong mau so cac phan so sau:
a, 2/3 va 17/81=
b,11/16 va 11/12=
c,5/7;7/5 va 31/35=
tim 1 phan so bang phan so 31 / 45 , biet phan so can tim co tu sova mau so deu la cac so co 2 chu so
Cho phan so 31/45.Tim mot so tu nhien sao cho khi dem tu so cong voi so do va giu nguyen tu thi ta dc phan so moi co gia tri =8/9
Tính :
2/5 + 11/15 =
7/8 - 7/9 =
11/13 x 26/31 =
16/24 : 4 =
30 : 6/5 =
9/16 : 4 =
1/2 : 1/3 x 8/15 =
hay dien tiep vao o trong so thu tam trong day sau la 3,6,15,42,123
tinh nhanh
a 1/4 + 2/5 + 6/8 + 9/15 + 8/1 b . 15/31 * 16/43 + 15/31 * 27/43