\(B=\frac{5}{30}+\frac{15}{90}+\frac{25}{150}+\frac{35}{210}+\frac{45}{270}\)
\(B=\frac{1}{6}+\frac{1}{6}+\frac{1}{6}+\frac{1}{6}+\frac{1}{6}=\frac{5}{6}\)
Tính bằng cách thuận tiện
Q=5/30+15/90+25/150+35/210+45/270
Tính :
a) \(\frac{16.17-5}{16.16+11}\)
b) \(\frac{5}{30}+\frac{15}{90}+\frac{25}{150}+\frac{35}{210}+\frac{45}{270}\)
Tính nhanh:
a)\(\frac{5}{30}+\frac{15}{90}+\frac{25}{150}+\frac{35}{210}+\frac{45}{270}\)
b)\(\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+\frac{1}{20}+...+\frac{1}{56}\)
c)\(\frac{1}{15}+\frac{4}{30}+\frac{2}{45}+\frac{16}{60}+\frac{25}{75}+\frac{36}{90}+\frac{49}{105}+\frac{64}{120}+\frac{81}{135}\)
25 2/13 -(15/17+ 15 2/3)
5/30 + 15/90+250/150+350/210+45/270
3 1/11 nhân 27/46 nhân 1 6/17 nhân 2 4/9
tính giá trị biểu thức một cách hợp lý
\(\dfrac{5}{30}\)+\(\dfrac{15}{90}\)+\(\dfrac{25}{150}\)+\(\dfrac{35}{210}\)+\(\dfrac{45}{270}\)
\(\frac{1}{5}+\frac{4}{10}+\frac{9}{15}+\frac{16}{20}+\frac{25}{25}+\frac{36}{30}+\frac{49}{35}+\frac{64}{40}+\frac{81}{45}\)=?
1/5+4/10+9/15+25/25+36/30+49/35+64/40+81/45
tìm các số tự nhiên x bít
a, ( x - 140 ) :35 = 270
b, 180 - ( x - 45 ) : 2 = 120
c, 25 . x - 100 = 150
d,( x + 200 ) : 4 = 460 + 85.4
e, 1 + 3 + 5 + 7 + .... + x = 25
help
1/5+4/10+9/15+16/20+25/25+36/30+49/35+64/60+81/45