tong la:
(197+1)x [(197-1):4+1]:2=4950
dap so 4950
nha ban
chuc ban hoc gioi
tong la:
(197+1)x [(197-1):4+1]:2=4950
dap so 4950
nha ban
chuc ban hoc gioi
5+3=28
9+1=810
8+9=214
5+4=19
7+2=?
tính nhanh:
a) 1+5+9+...+197+201+205
b) 2+5+8+11+...+185+188
tính nhanh:
a) 1+5+9+...+197+201+205
b) 2+5+8+11+...+185+188
\(\frac{\text{234 x 76 + 117 x 48 + 234 x 425}}{1+5+9+.....+193+197}\)
3/1x2-5/2x3+7/3x4-9/4x5+.......-197/98x99
Tính bằng cách thuận tiện nhất:
\(\frac{234.76+117.48+234.245}{1+5+9+...+193+197}=\).....
Tính hợp lý:
A= 1+3+5+7+.............+2015
B=1+4+7+10+...........+2014
C=1+2+4+8+16+.........+2014
D=1+2-3-4+5+6-7-8+9+...................+197+198-199+200+201
234x76+117x48+234x425 ...................
----------------------------------- = ---------------
1+5+9+............+193+197 ..................
giup minh voi, minh con 4 tieng nua thoi la phai nop bai roi
1+3+5+7+... +197