Tính hợp lí:
3/5×(5/2 - 10/3) - 5/8 : (1/4-2/3)
Tính nhanh một cách hợp lí :
1/2 + 2/3 - 3/4 × 4/5 × 5/6 × 6/7 × 7/8 × 8/9 × ......................... × 29/30 : 6/10
1/2 + 2/3 - 3/4 * 4/5 * 5/6 * 6/7 * 7/8 * 8/9 *...* 29/30 : 6/10
= 1/2 + 2/3 - 1/10 : 6/10
= 1/2 + 2/3 - 1/6
= 1
Thực hiện phép tính(tính hợp lí nếu có thể)
4/5+(-5)/4 -1/3+2/5-5/6 2/3-5/7.14/25 (2/5-5/6):8/15-(-1)^2
-3/13+(-7)/17+(-5)/19+(-10)/13+24/17+(-14)/19
\(\dfrac{4}{5}\)+\(\dfrac{-5}{4}\)=\(\dfrac{0}{4}\)
\(\dfrac{-1}{3}\)+\(\dfrac{2}{5}-\dfrac{5}{6}\)=\(\dfrac{-10}{30}+\dfrac{12}{30}-\dfrac{25}{30}\)=\(\dfrac{-23}{30}\)
\(\dfrac{2}{3}-\dfrac{5}{7}.\dfrac{14}{25}\)=\(\dfrac{2}{3}-\dfrac{2}{5}\)=\(\dfrac{10}{15}-\dfrac{6}{15}\)=\(\dfrac{4}{15}\)
a: \(=\dfrac{16-25}{20}=\dfrac{-9}{20}\)
b: \(=\dfrac{-10}{30}+\dfrac{12}{30}-\dfrac{25}{30}=-\dfrac{23}{30}\)
c: \(=\dfrac{2}{3}-\dfrac{1}{5}\cdot2=\dfrac{2}{3}-\dfrac{2}{5}=\dfrac{10-6}{15}=\dfrac{4}{15}\)
d: \(=\dfrac{12-25}{30}\cdot\dfrac{15}{8}-1=\dfrac{-13}{16}-1=\dfrac{-29}{16}\)
e: \(=\dfrac{-3}{13}-\dfrac{10}{13}-\dfrac{7}{17}+\dfrac{24}{17}-\dfrac{5}{19}-\dfrac{14}{19}=-1\)
Thực hiện phép tính ( tính hợp lí nếu có thể)
-4/11 . 2/5 + 6/11 . -3/10
1/7 - 8/7 : 8 - 3 : 3/4 . ( -2)2
1/3 . 4/5 + 1/3 .6/5-4/3
1. Tính hợp lí:
a) B = 1/2 - [ 3/8 + ( -7/4 ) ]
b) -4/12 - ( -13/39 - 0,25 ) + 0,75
c) 1/2 - 1/3 + 1/23 + 1/6
d) ( -13/7 - 4/9) - ( -10/7 - 4/9 )
e) ( 7/8 - 5/2 + 4/7 ) - ( -3/7 + 1 - 13/8 )
f) -3/7 + ( 3 - 3/4 ) - ( 2,25 - 10/7)
g) ( 5/3 - 3/7 + 9 ) - ( 2 + 5/7 - 2/3 ) + ( 8/7 - 4/3 - 10 )
Thực hiện phép tính( tính hợp lí nếu có thể)
1) 14.25-28/7.19+28
2)27 3/5:12/5+12 2/5:2 2/5
3) 50%.1 1/3.10.7/35.0,75
4)2/3+1/3(-4/9+5/6):7/12
5) 2^2+10^3:10-(3^2.112:8-11).2005^0
6)[(6 3/5-3 3/14).5 5/6]:[(21-1,25):2,5]
7)2/3+2/7-1/14/-1-3/7+3/28
Mk ko ghi lại đề nhé
1 = \(350-4.19+4.7\)
\(=350-4.\left(19+7\right)\)
\(=350+4.26\)
\(=350-104=246\)
2 Câu này mình vẫn chưa hiểu là bạn ghi 27 3/5 tức là 27.3/5 hay 27\(\dfrac{3}{5}\)nên mk bỏ qua nhé
3 Cái đoạn 1 1/3 y chang câu 2
4 \(=\dfrac{2}{3}+\dfrac{1}{3}.\dfrac{7}{18}.\dfrac{12}{7}\)
\(=\dfrac{2}{3}+\dfrac{7}{54}.\dfrac{12}{7}\)
\(=\dfrac{2}{3}+\dfrac{2}{9}=\dfrac{8}{9}\)
5 \(=2^2+10^2-\left[9.\left(112:8\right)-11\right].1\)
\(=4+100-\left(9.14-11\right)\)
\(=104-115\)\(=-11\)
6 Đoạn 6 3/5 y chang 2,3
7 \(=\left(\dfrac{2}{3}-1\right)+\left(\dfrac{2}{7}-\dfrac{3}{7}\right)-\left(\dfrac{1}{14}-\dfrac{3}{28}\right)\)
\(=\dfrac{-1}{3}+\dfrac{-1}{7}-\dfrac{-1}{28}\)
\(=\dfrac{-196}{588}+\dfrac{-84}{588}-\dfrac{-21}{588}\)\(=\dfrac{259}{588}\)
Làm tạm tạm thôi xl vì có 3 câu ko hiểu
Tính hợp lí.
A=(-4/5 +4/3) +(-5/4 +14/5) - 7/3
B= 8/3 . 2/5 .3/8 .10 .19/92
Giúp mình với,please 🙇🙇
Tính hợp lí.
A=(-4/5 +4/3) +(-5/4 +14/5) - 7/3
B= 8/3 . 2/5 .3/8 .10 .19/92
Giúp mình với,please 🙇🙇
\(A=\left(-\frac{4}{5}+\frac{4}{3}\right)+\left(-\frac{5}{4}+\frac{14}{5}\right)-\frac{7}{3}\)
\(=-\frac{4}{5}+\frac{4}{3}-\frac{5}{4}+\frac{14}{5}-\frac{7}{3}\)
\(=2-1-\frac{5}{4}=-\frac{1}{4}\)
\(B=\frac{8}{3}\cdot\frac{2}{5}\cdot\frac{3}{8}\cdot10\cdot\frac{19}{92}\)
\(=1\cdot4\cdot\frac{19}{92}\)
\(=437\)
chúng mày ngu như dog ý câu dễ thế ko biết làm
Tính bằng cách hợp lí:
5/8 + 2/9 - 2/5 +3/8 + 4/9 +1/3 - 3/5=
\(\frac{5}{8}+\frac{2}{9}-\frac{2}{5}+\frac{3}{8}+\frac{4}{9}+\frac{1}{3}-\frac{3}{5}\)
\(=\frac{5}{8}+\frac{2}{9}-\frac{2}{5}+\frac{3}{8}+\frac{4}{9}+\frac{3}{9}-\frac{3}{5}\)
\(=\left(\frac{5}{8}+\frac{3}{8}\right)+\left(\frac{2}{9}+\frac{4}{9}+\frac{3}{9}\right)-\left(\frac{2}{5}+\frac{3}{5}\right)\)
\(=\frac{8}{8}+\frac{9}{9}-\frac{5}{5}\)
\(=1+1-1\)
\(=2-1\)
\(=1\)
Tính bằngcách hợp lí: 2/5+2/11-2/9 trên 7/5-7/9+7/11:1/3-1/4+1/5 trên 7/6-7/8+7/10