Tính :
a) \(1\frac{7}{20}:2,7+2,7:1,35+\left(0,4:2\frac{1}{2}\right).\left(4,8-1\frac{3}{40}\right)\)
b) \(\left[\left(6\frac{3}{5}-3\frac{3}{14}\right):5\frac{5}{6}\right]:\left[\left(21-1,25\right):2,5\right]\)
K
Khách
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
Những câu hỏi liên quan
NX
20 tháng 8 2016
\(B=1x\frac{7}{20}:2,7+2,7:1,35+\left(0,4+2\frac{1}{2}\right)x\left(4,2-1\frac{3}{10}\right)\)
\(B=\frac{7}{20}:2,7+2+2,9x2,9\)
\(B=\frac{7}{54}+2+8,41\)
\(B=10,53962963\)
HQ
Hà Quang Minh
Giáo viên
19 tháng 9 2023
a)
\(\begin{array}{l}0,75 - \frac{5}{6} + 1\frac{1}{2} = \frac{3}{4} - \frac{5}{6} + \frac{3}{2}\\ = \frac{9}{{12}} - \frac{{10}}{{12}} + \frac{{18}}{{12}} = \frac{{17}}{{12}}\end{array}\)
b)
\(\begin{array}{l}\frac{3}{7} + \frac{4}{{15}} + \left( {\frac{{ - 8}}{{21}}} \right) + \left( { - 0,4} \right) = \frac{3}{7} + \frac{4}{{15}} - \frac{8}{{21}} - \frac{2}{5}\\ = \left( {\frac{3}{7} - \frac{8}{{21}}} \right) + \left( {\frac{4}{{15}} - \frac{2}{5}} \right)\\ = \left( {\frac{9}{{21}} - \frac{8}{{21}}} \right) + \left( {\frac{4}{{15}} - \frac{6}{{15}}} \right)\\ = \frac{1}{{21}} + \left( {\frac{{ - 2}}{{15}}} \right)\\ = \frac{5}{{105}} - \frac{{14}}{{105}}\\ = \frac{{ - 9}}{{105}} = \frac{{ - 3}}{{35}}\end{array}\)
c)
\(\begin{array}{l}0,625 + \left( {\frac{{ - 2}}{7}} \right) + \frac{3}{8} + \left( {\frac{{ - 5}}{7}} \right) + 1\frac{2}{3}\\ = \frac{5}{8} + \left( {\frac{{ - 2}}{7}} \right) + \frac{3}{8} - \frac{5}{7} + \frac{5}{3}\\ = \left( {\frac{5}{8} + \frac{3}{8}} \right) + \left( {\frac{{ - 2}}{7} - \frac{5}{7}} \right) + \frac{5}{3}\\ = 1 - 1 + \frac{5}{3} = \frac{5}{3}\end{array}\)
d)
\(\begin{array}{l}\left( { - 3} \right).\left( {\frac{{ - 38}}{{21}}} \right).\left( {\frac{{ - 7}}{6}} \right).\left( { - \frac{3}{{19}}} \right)\\ = \frac{{ - 3.\left( { - 38} \right).\left( { - 7} \right).\left( { - 3} \right)}}{{21.6.19}}\\ = \frac{{3.38.7.3}}{{21.6.19}}\\ = \frac{{3.2.19.7.3}}{{3.7.3.2.19}}\\ = 1\end{array}\)
e)
\(\begin{array}{l}\left( {\frac{{11}}{{18}}:\frac{{22}}{9}} \right).\frac{8}{5} = \left( {\frac{{11}}{{18}}.\frac{9}{{22}}} \right).\frac{8}{5}\\ = \frac{{11.9.4.2}}{{9.2.2.11.5}} = \frac{2}{5}\end{array}\)
g)
\(\left[ {\left( {\frac{{ - 4}}{5}} \right).\frac{5}{8}} \right]:\left( {\frac{{ - 25}}{{12}}} \right) = \frac{{ - 20}}{{40}}:\left( {\frac{{ - 25}}{{12}}} \right)\\ = \frac{{ - 1}}{2}.\frac{{ - 12}}{{25}} = \frac{6}{{25}}\)
VM
17 tháng 9 2019
a) \(-6.\left(-\frac{2}{3}\right).0,25\)
\(=-6.\left(-\frac{2}{3}\right).\frac{1}{4}\)
\(=4.\frac{1}{4}\)
\(=1.\)
b) \(-\frac{15}{4}.\left(-\frac{7}{15}\right).\left(-2\frac{2}{5}\right)\)
\(=-\frac{15}{4}.\left(-\frac{7}{15}\right).\left(-\frac{12}{5}\right)\)
\(=\frac{7}{4}.\left(-\frac{12}{5}\right)\)
\(=-\frac{21}{5}.\)
c) \(\left(-0,4\right)^2-\left(-0,4\right)^3.\left(-3\right)\)
\(=0,16-\left(-0,064\right).\left(-3\right)\)
\(=0,16-0,192\)
\(=-0,032.\)
Chúc bạn học tốt!
8 tháng 6 2017
\(A=-\frac{550}{9}\)\(\Rightarrow\)12.5% của A là \(\frac{-275}{36}\)
\(B=\frac{2}{5}\Rightarrow\)5% của B là \(\frac{1}{8}\)
