Tính nhanh ( nếu có thể ):
1399:1397+4.42-20150
Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.
78 :76 + 4.42 - 13
= 72 + 43 - 13
= 49 + 64 - 13
= 113 - 13
= 100
1397.1397
=1397(1+1)
=1397.2
=2794
lozzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzzz
1397 . 1397 = 13972 = 1951609
Học tốt!!!
a) 1 2 4 − 1 4 2 . 5 19 + 5 12 − 3 4 : 1 6 = 1 16 − 1 16 . 5 19 + 5 12 − 9 12 : 1 6 = 0 + − 4 12 : 1 6 = − 1 3 .6 = − 2.
b) 25% − 1 1 2 . − 2015 0 + 0,5. 12 5 = 1 4 − 3 2 .1 + 1 2 . 12 5 = 1 4 − 3 2 + 12 10 = 5 20 − 30 20 + 24 20 = − 1 20 .
13: \(\left(-15\right)+8+7\)
\(=\left(-15\right)+\left(8+7\right)\)
=-15+15
=0
14: \(\left(-8\right)+2+6\)
\(=\left(-8\right)+\left(2+6\right)\)
=-8+8
=0
15: \(\left(-1\right)+3-2\)
\(=\left(-1-2\right)+3\)
=-3+3
=0
16: \(25-8-7\)
\(=25-\left(8+7\right)\)
=25-15
=10
17: \(8-2-6\)
\(=8-\left(2+6\right)\)
=8-8
=0
18: \(\left(-12\right)-3+15\)
\(=\left(-12-3\right)+15\)
=-15+15
=0
\(8)\) \(( -6,2 :2 + 3,7 ) : 0,2 = ( -3,1 + 3,7 ) : 0,2 = 0,6 : 0,2 = 3\)
\(9) \) \( 4 \dfrac{11}{23} - \dfrac{9}{14} + 2 \dfrac{12}{23} - \dfrac{5}{14}\)
\(= ( 4 \dfrac{11}{23} + 2 \dfrac{12}{23}) - ( \dfrac{5}{14} + \dfrac{9}{14} )\)
\(= 8- \dfrac{14}{14} \)
\(= 8-1\)
\(=7\)
\(10)\) \(11 \dfrac{1}{4} - ( 2 \dfrac{5}{7} + 5\dfrac{1}{4} )\)
\(= 11 \dfrac{1}{4} - 2 \dfrac{5}{7} - 5\dfrac{1}{4} \)
\(= 11 \dfrac{1}{4} - 5\dfrac{1}{4} - 2 \dfrac{5}{7}\)
\(= 6 - \dfrac{19}{7} = \dfrac{42}{7} - \dfrac{19}{7} = \dfrac{23}{7}\)
Lời giải:
$=\frac{81}{20}.\frac{4}{9}+\frac{4}{15}: \frac{-4}{7}$
$=\frac{9.9.4}{4.5.9}+\frac{4}{15}.\frac{-7}{4}$
$=\frac{9}{5}+\frac{-7}{15}=\frac{27}{15}+\frac{-7}{15}=\frac{20}{15}=\frac{4}{3}$
\(\dfrac{50-\dfrac{6}{13}+\dfrac{3}{19}-\dfrac{3}{23}}{100-\dfrac{12}{13}+\dfrac{6}{19}-\dfrac{6}{23}}\)
\(=\dfrac{50-\dfrac{6}{13}+\dfrac{3}{19}-\dfrac{3}{23}}{2\left(50-\dfrac{6}{13}+\dfrac{3}{19}-\dfrac{3}{23}\right)}\)
\(=\dfrac{1}{2}\)
1399:1397+4.42-20150
= 132 + 43 - 1
= 169 + 64 -1