Tính bằng cách thuận tiện nhất:
69,78 + 35,97 x 3,2 : 1,5
Tính bằng cách thuận tiện nhất 69,78 +35,97 + 30,22
Tính bằng cách thuận tiện nhất: 69,78 + 35,97 + 30,22
69,78 + 35,97 + 30,22 = (69,78 + 30,22) + 35,97=100 + 35,97=135,97
( 69,78+30,22)+35,97
100+35,97
135,97
cho m nha
Tích bằng cách thuận tiện nhất
a)69,78 + 35,97 + 30,22 =...............
b)83,45 - 30,98 - 42,47 =.................
a)69,78 + 35,97 + 30,22
=(69,78+30,22)+35,97
=100 + 35,97
=135,97
b)83,45 - 30,98 - 42,47
=83,45-(30,98+42,47)
=83,45-73,45
=10
a) (69,78+30,22)+35,97
=100+35,97
=135,97
tính bằng cách thuận tiện
72/99-28/99-14/99
69,78+35,97+30,22
83,45-30,98-42,47
\(\frac{72}{99}-\frac{28}{99}-\frac{14}{99}=\frac{72-28-14}{99}\)\(=\frac{30}{99}=\frac{10}{33}\)
\(\left(69,78+30,22\right)+35,97\)\(=100+35,97=135,97\)
\(83,45-\left(30,98+42,47\right)\)\(=83,45-73,45=10\)
72/99-28/99-14/99
=72/99-(28/99+14/99)
=72/99-42/99
=30/99=10/33
67,78+35,97+30,22
=(67,78+30,22)+35,97
=98+35,97
=133,97
83,45-30,98-42,47
=83,45-(30,98+42,47)
=83,45-73,45
=10
tính bằng cách thuận tiện nhất :
a) 7/11 + 3/4 + 4/11 + 1/4
b)72/99 - 28/99 - 14/99
c)69,78 + 35,97 + 30,22
d)83,45 - 30,98 - 42,47
a) 7/11+3/4+4/11+1/4
=(7/11+4/11)+(3/4+1/4)
= 1 + 1
= 2.
b) 72/99-28/99-14/99
=72/99-(28/99+14/99)
=72/99- 42/99
= 30/99=10/33.
c) 69,78+35,97+30,22
=(69,78+30,22)+35,97
= 100 +35,97
= 135,97.
d) 83,45-30,98-42,47
=83,45-(30,98+42,47)
=83,45- 73,45
= 10.
a: (7/11+4/11)+(3/4+1/4)
=11/11+4/4
=1+1=2
b: 72/99-28/99-14/99
=72/99-(28/99+14/99)
=72/99-42/99
=30/99
=10/33
c: 69,78+35,97+30,22
=(69,78+30,22)+35,97
=100+35,97
=135,97
d :83,45-(30,98+42,47)
=83,45-73,45
=10
Tính bằng cách thuận tiện nhất:
a) \(\dfrac{7}{11}+\dfrac{3}{4}+\dfrac{4}{11}+\dfrac{1}{4}\); b) \(\dfrac{72}{99}-\dfrac{28}{99}-\dfrac{14}{99}\);
c) \(69,78+35,97+30,22\); d) \(83,45-30,98-42,47\)
a) \(\dfrac{7}{11}+\dfrac{3}{4}+\dfrac{4}{11}+\dfrac{1}{4}=\left(\dfrac{7}{11}+\dfrac{4}{11}\right)+\left(\dfrac{3}{4}+\dfrac{1}{4}\right)=1+1=2\)
b) \(\dfrac{72}{99}-\dfrac{28}{99}-\dfrac{14}{99}=\dfrac{72-28-14}{99}=\dfrac{30}{99}=\dfrac{10}{33}\)
c) \(69.78+35.97+30.22=\left(69.78+30.22\right)+35.97=100+35.97=135.97\)
Tính bằng cách thuận tiện nhất :
a. 69,78 x \(\dfrac{3}{4}\) + 69,78 x \(\dfrac{1}{4}\) + 69,78 x 99
b. 34,1 x 8 + 34,1 x 0,5
\(a,=69,78\times\left(\dfrac{3}{4}+\dfrac{1}{4}+99\right)\\ =69,78\times\left(\dfrac{4}{4}+99\right)\\ =69,78\times\left(1+99\right)=69,78\times100=6978\\ b,34,1\times8+34,1\times0,5\\ =34,1\times\left(8+0,5\right)\\ =34,1\times8,5\\ =289,85\)
a: =69,78(3/4+1/4+99)
=69,78*100
=6978
b: =34,1(8+0,5)=34,1*8,5=289,85
a.\(69,78\times\dfrac{3}{4}+69,78\times\dfrac{1}{4}+69,78\times99=69,78\times\left(\dfrac{3}{4}+\dfrac{1}{4}+99\right)=69,78\times100=6978\)
b. \(34,1\times8+34,1\times0,5=34,1\times\left(8+0,5\right)=34,1\times8,5=289,85\)
Tính bằng cách thuận tiện:
69,78 x 75% + 69,78 x \(\frac{1}{4}\)+ 69,78 x 99
TL:
=69,78 x (75% + 1/4 + 99)
=69,78 x (3/4 + 1/4 + 99)
= 69,78 x (1 + 99)
= 69,78 x 100
= 6978
HT
69,78 x 75% + 69,78 x \(\frac{1}{4}\) + 69,78 x 99
= 69,78 x 7,5 + 69,78 x 0,25 + 69,78 x 99
= 69,78 x ( 99 + 7,5 + 0,25 )
= 69,78 x 100
= 6978
tính bằng cách thuận tiện nhất
7/11 + 3/4 + 4/11 + 1/4 72/99 - 28/99 - 14/99
69,78 + 35,97 + 30,22 83,45 - 30,98 - 42,47
7/11+3/4+4/11+1/4=(7/11+4/11)+(3/4+1/4)=1+1=2
\(\frac{7}{11}+\frac{3}{4}+\frac{4}{11}+\frac{1}{4}\)
\(=\left(\frac{7}{11}+\frac{4}{11}\right)+\left(\frac{3}{4}+\frac{1}{4}\right)\)
= 1 + 1
= 2
\(\frac{72}{99}-\frac{28}{99}-\frac{14}{99}\)
\(=\frac{72}{99}-\left(\frac{28}{99}+\frac{14}{99}\right)\)
\(=\frac{72}{99}-\frac{42}{99}\)
\(=\frac{30}{99}=\frac{10}{33}\)