1/3 + 13/15 + 33/35 + 61/63 + 97/99
1717/1919*303/1818+17/19*1515/1818
tính nhanh \(A=\frac{1717}{1919}\times\frac{303}{1818}+\frac{17}{19}\times\frac{1515}{1818}\)
\(A=\frac{17}{19}x\frac{1}{6}+\frac{17}{19}x\frac{5}{6}\)
\(=\frac{17}{19}x\left(\frac{1}{6}+\frac{5}{6}\right)=\frac{17}{19}x1=\frac{17}{19}\)
A= \(\frac{1717}{1919}\text{ *}\frac{303}{1818}+\frac{17}{19}\text{ *}\frac{1515}{1818}\)
A= \(\frac{17}{19}\text{ *}\frac{3}{18}+\frac{17}{19}\text{ *}\frac{15}{18}\)
A= \(\frac{17}{19}\text{ *}\left(\frac{3}{18}+\frac{15}{18}\right)\)
A= \(\frac{17}{19}\text{ *}1\)
A= \(\frac{17}{19}\)
Vậy A= \(\frac{17}{19}\)
vVv Học tốt nhé bạn, mình sẽ rất vui nếu bạn k đúng cho mình, cảm ơn ban nhiều vVv
\(\frac{1717}{1919}x\frac{303}{1818}+\frac{17}{19}x\frac{1515}{1818}\)
= \(\frac{17}{19}x\frac{1}{6}\)+ \(\frac{17}{19}x\frac{5}{6}\)
= \(\frac{17}{19}\)x ( \(\frac{1}{6}+\frac{5}{6}\))
= \(\frac{17}{19}x1\)
= \(\frac{17}{19}\)
1717\1919×303\1818+1717\1919×1515\1818
tính giá trị biểu thức : A =1717/1919 * 303/1818 + 1717/1919 * 1515/1818
\(\frac{1717}{1919}.\frac{303}{1818}+\frac{1717}{1919}.\frac{1515}{1818}\)
\(=\frac{1717}{1919}.\left(\frac{303}{1818}+\frac{1515}{1818}\right)\)
\(=\frac{1717}{1919}.1\)
\(=\frac{17}{19}\)
Dấu "." là dấu " x "
học tốt!!!
\(A=\frac{17\cdot101}{19\cdot101}\cdot\frac{1\cdot303}{6\cdot303}+\frac{17\cdot101}{19\cdot101}\cdot\frac{5\cdot303}{6\cdot303}\)
\(=\frac{17}{19}\cdot\frac{1}{6}+\frac{17}{19}\cdot\frac{5}{6}\)
\(=\frac{17}{19}\cdot\left(\frac{5}{6}+\frac{1}{6}\right)\)
\(=\frac{17}{19}\cdot1\)
\(=\frac{17}{19}\)
1/3 + 1/15 + 1/35+ 1/63 + 1/99+ 1/143+ 1/195
b) \(\frac{1414+1515+1616+1717+1818+1919}{2020+2121+2222+2323+2424+2525}\)
Ai biết làm bài này thì giúp mik nhé
Để mình giúp bạn nha !!!
A) \(\frac{7}{15}\)
B) 4,391
1\3+1\15+1\35+1\63+1\99+1\143=1\195
1414+1515+1616+1717+1818+1919
2020+2121+2323+2424+2525
2 tim x
( 7*13+8*13):(29\3 tru x) bang 39
1\3+1\6+1\10+.....+2\x*(x+1) bang 2011\203
SO sánh 1414+1515+1616+1717+1818+1919 với 11
2020+2121+2222+2323+2424+2525 15
Vì 14/14 = 1; 15/15 = 1 ; ....
⇔ Tổng trên là 6 < 11.
Vì 20/20 = 1 ; 21/21 = 1 ; ...
⇒ Tổng trên là 6 < 15.
tính nhanh H = 1414 + 1515 + 1616 + 1717 + 1818 + 1919
SO sánh 1414+1515+1616+1717+1818+1919/2020+2121+2222+2323+2424+2525 với 11/15 trả lời cho mình nha đang cần gấp
A = \(\dfrac{1414+1515+1616+1717+1818+1919}{2020+2121+2022+2323+2424+2525}\)
A = \(\dfrac{101\times\left(14+15+16+17+18+19\right)}{101\times\left(20+21+22+23+24+25\right)}\)
A = \(\dfrac{99}{135}\)
A = \(\dfrac{11}{15}\)
1414+1515+1616+1717+1818+1919/2020+2121+2222+2323+2424+2525
Đề bài kiểu gì vậy?VIết rõ hơn đi
1414+1515+1616+1717+1818+1919
2020+2121+2222+2323+2424+2525