27+4/3=81/3+4/3=85/3
27-4/3=81/3-4/3=77/3
27+4/3=81/3+4/3=85/3
27-4/3=81/3-4/3=77/3
Tính nhanh:
2/3 x 4/5 + 4/5 x 8/3 27/32 x 16/9 - 27/32 x 7/9 + 27/32
A=2/3*5 + 2/5*7 + 2/7*9 + 2/9*11 + 2/11*13 + 2/11*15
B=2/1*2 + 2/2*3 + ..........+2/9*10
Giup mình theo kiểu bài như dưới đây nhé :
D =4/3*7 + 4/7*11 + 4/11*15 +............. + 4/23*27
D=7/3*7 - 3/3*7 + 11/7*11 + ................. + 23/23*27
D=1/3 -1/7 +1/7 - ................. - 1/27
D= 1/2 - 1/27
D= 8/27
Bài 2. > , < , = ?
5/7… 4/3 2/5 …… 6/10 1/4 …… 3/12 27/36 ….. 2/9 7/6 …… 7/9
7/2 …… 2/7 15/23........1 27/9.......2 14/15........1 51/17........4
3(1/11) x 27(27/46) x 1(6/17) x 2(4/7)=....
3 1/11 * 27 27/46 * 1 6/ 17 * 2 4/9
3(1/11) x 27(27/46) x 1(6/17) x 2(4/9)=
4-(27-3)=x-(13-4)
tinh tong cua day so sau
1+2+3+4...+25+26+27+27
Tính nhanh:
37 x 27 + 63 x 27
1+2+3+4+...+97+98+99
1+2+3+4+5+6+7+8+9+10