B= 1/3 + 5/6 + 11/12 + 19/20 + 29/30 (tính nhanh) 29/11/2021 Bởi Amara B= 1/3 + 5/6 + 11/12 + 19/20 + 29/30 (tính nhanh)
Đáp án: B=4 Giải thích các bước giải: B=1/3+5/6+11/12+19/20+29/30 B= 20/60+50/60+55/60+57/60+58/60 B=240/60 B=4 Bình luận
Ta có : $\dfrac{1}{3}+\dfrac{5}{6}+\dfrac{11}{12}+\dfrac{19}{20}+\dfrac{29}{30}$ $ = \dfrac{7}{6} + \dfrac{11}{12}+\dfrac{19}{20}+\dfrac{29}{30}$ $ = 1 + \dfrac{1}{6}+\dfrac{11}{12}+\dfrac{19}{20}+\dfrac{29}{30}$ $ = 1 + (\dfrac{11}{12}+\dfrac{1}{12})+(\dfrac{19}{20}+\dfrac{1}{20})+(\dfrac{29}{30}+\dfrac{1}{30})$ ( Giải thích : Vì : $\dfrac{1}{6} = \dfrac{1}{12}+\dfrac{1}{20}+\dfrac{1}{30} $ ) $ = 1+1+1+1=4$ Vậy $\dfrac{1}{3}+\dfrac{5}{6}+\dfrac{11}{12}+\dfrac{19}{20}+\dfrac{29}{30} = 4$ Bình luận
Đáp án:
B=4
Giải thích các bước giải:
B=1/3+5/6+11/12+19/20+29/30
B= 20/60+50/60+55/60+57/60+58/60
B=240/60
B=4
Ta có :
$\dfrac{1}{3}+\dfrac{5}{6}+\dfrac{11}{12}+\dfrac{19}{20}+\dfrac{29}{30}$
$ = \dfrac{7}{6} + \dfrac{11}{12}+\dfrac{19}{20}+\dfrac{29}{30}$
$ = 1 + \dfrac{1}{6}+\dfrac{11}{12}+\dfrac{19}{20}+\dfrac{29}{30}$
$ = 1 + (\dfrac{11}{12}+\dfrac{1}{12})+(\dfrac{19}{20}+\dfrac{1}{20})+(\dfrac{29}{30}+\dfrac{1}{30})$
( Giải thích : Vì : $\dfrac{1}{6} = \dfrac{1}{12}+\dfrac{1}{20}+\dfrac{1}{30} $ )
$ = 1+1+1+1=4$
Vậy $\dfrac{1}{3}+\dfrac{5}{6}+\dfrac{11}{12}+\dfrac{19}{20}+\dfrac{29}{30} = 4$