Tính hợp lí
-11 x 107 + 11 x 18 - 11 x 11
tính hợp lí:
a, ( -18 ) + ( -31 ) + 98 + |-18| + ( -69 )
b, 15 x ( -176 ) + 15 x 76 + 100 x 15
c, 79 x 89 - 79 x (-11) - 100 x 79
a) (-18)+(-31)+98+|-18|+(-69)
((-18)+98)+((-31)+18+(-69))
80+ (-82)
-2
b)15×(-176)+15×76+100×15
=15×((-176)+76+10)
=15×0
=0
c)79×89-79×(-11)-100×79
=79×(89-(-11)-100)
=79×0
=0
Chúc bạn học tốt
a) (-18)+(-31)+98+|-18|+(-69)
=(-18)+(-31)+98+18+(-69)
=[(-18)+18]+[(-31)+(-69)]+98
=0+(-100)+98
=-2
b) 15.(-176)+15.76+100.15
=15[(-176)+76+100]
=15.0=0
c) 79.89-79.(-11)-100.79
=19.[89-(-11)-100]
=19.0=0
a, -18-31+98+18-69=(-18+18)-(31+69)+98= -100+98= -2
b, 15 x (-176+76+100)= 15 x 0 = 0
c, 79 x (89+11-100)= 79 x 0=0
THE END
Tính bằng cách hợp lí nhất
A, 18/11 x 22/19 z 38/9
B, 4/7 x 2/5 + 2/5 x 9/7 + 8/7 x 2/5
A ) \(=\dfrac{2\times9\times11\times2\times19\times2}{11\times19\times9}=\dfrac{8}{1}=8\)
b)\(=\dfrac{2}{5}\times\left(\dfrac{4}{7}+\dfrac{9}{7}+\dfrac{8}{7}\right)=\dfrac{2}{5}\times\dfrac{21}{7}=\dfrac{2}{5}\times3=\dfrac{6}{5}\)
Tính hợp lí nếu có thể
1/9 x 4/11 + 3/4 + 7/11 x 1/9
1/9 x 4/11 + 3/4 +7/11 x 1/9
= 1/9 x (4/11 + 7/11) + 3/4
= 1/9 x 1 + 3/4
=1/9 + 3/4
= 31/36
gyyeshqadfghfgddsfsafasfdfdddsfdsdasdsdafffffffffffffffffffffffffffffffffffffffffffffffffffffff | |||||||||
\(\frac{1}{9}x\frac{4}{11}+\frac{3}{4}+\frac{7}{11}x\frac{1}{9}\)
\(=\frac{1}{9}x\left(\frac{4}{11}+\frac{7}{11}\right)+\frac{3}{4}\)
\(=\frac{1}{9}x1+\frac{3}{4}\)
\(=\frac{1}{9}+\frac{3}{4}\)
\(=\frac{31}{36}\)
\(\text{Hok tốt!}\)
\(\text{@Kaito Kid}\)
Tính hợp lí :
B = 5 / 2 x1 + 4 / 1x 11 + 3 / 11 x 2 + 1 /2x15 + 13 / 15 x 4
trả lời:
B = 7x( 5/2x7 + 4/7x11 + 3/11x14 + 1/14x15 + 13/15x28 )
B = 7x(1/2 - 1/7 + 1/7 - 1/11 +....+ 1/15 - 1/28)
B = 7x(1/2 - 1/28)
B = 7x13/28
B = 13/4
Bàì làm:
\(B=\frac{5}{2.1}+\frac{4}{1.11}+\frac{3}{11.2}+\frac{1}{2.15}+\frac{13}{15.4}\)
\(B=7.\left(\frac{5}{2.7}+\frac{4}{7.11}+\frac{3}{11.14}+\frac{1}{14.15}+\frac{13}{15.28}\right)\)
\(B=7.\left(\frac{1}{2}-\frac{1}{7}+\frac{1}{7}-\frac{1}{11}+\frac{1}{11}-\frac{1}{14}+\frac{1}{14}-\frac{1}{15}+\frac{1}{15}-\frac{1}{28}\right)\)
\(B=7.\left(\frac{1}{2}-\frac{1}{28}\right)\)
\(B=7.\frac{13}{28}\)
\(B=\frac{13}{4}\)
Bài làm:
\(B=\frac{5}{2.1}+\frac{4}{1.11}+\frac{3}{11.2}+\frac{1}{2.15}+\frac{13}{15.4}\)
\(B=7\left(\frac{5}{2.7}+\frac{4}{7.11}+\frac{3}{11.14}+\frac{1}{14.15}+\frac{13}{15.28}\right)\)
\(B=7\left(\frac{1}{2}-\frac{1}{7}+\frac{1}{7}-\frac{1}{11}+\frac{1}{11}-\frac{1}{14}+\frac{1}{14}-\frac{1}{15}+\frac{1}{15}-\frac{1}{28}\right)\)
\(B=7\left(\frac{1}{2}-\frac{1}{28}\right)=7.\frac{13}{28}=\frac{13}{4}\)
1. Tính hợp lí
-5/9 x 3/11 + -3/18 x 3/11 =
2. Tìm X biết:
2/3 + 7/4 : X = 5/6
Mình sẽ tick cho bạn nào giúp mình trong ngày hôm nay!
1.Tính hợp lí:
-5/9.3/11+(-3/18).3/11
=3/11.[(-5/9)+(-3/18)]
=3/11.-13/18
=-39/198
=13/66
2.Tìm x biết:
2/3+7/4:x=5/6
7/4:x=5/6-2/3
7/4:x=1/6
x=7/4:1/6
x=21/2
bài 1
\(\frac{-5}{9}.\frac{3}{11}+\frac{-3}{18}.\frac{3}{11}\)
= \(\frac{3}{11}.\left(\frac{-5}{9}+\frac{-3}{18}\right)\)
= \(\frac{-13}{66}\)
bài 2
\(\frac{2}{3}+\frac{7}{4}:x=\frac{5}{6}\)
\(\frac{7}{4}:x=\frac{1}{6}\)
\(x=\frac{21}{2}\)
Tính hợp lí:
A= -5/7 x 2/11 + -5/7 x 9/11 +1/5/7
kb với mk nha
A=-5/7x2/11+-5/7x9/11+1+5/7
A=5/7x-2/11+5/7x-9/11+1+5/7
A=5/7x[-2/11+-9/11+1]+1
A=5/7x0+1
A=0+1
A=1
A=\(\frac{-5}{7}\)x \(\frac{2}{11}\)+ \(\frac{-5}{7}\)x \(\frac{9}{11}\) + \(1\frac{5}{7}\)
A= \(\frac{-5}{7}\)x (\(\frac{2}{11}\)+ \(\frac{9}{11}\)) + \(\frac{12}{7}\)
A= \(\frac{-5}{7}\)x 1 + \(\frac{12}{7}\)
A= \(\frac{-5}{7}\)+ \(\frac{12}{7}\)
A= 1
tính bằng cách hợp lí nhất
a, ( 3 và 1/15 - 1/11 ) x 11
b, 1/7 x 1/91 x 1/247 x 1/775 x 1/1147