tính nhanh:
(792,81x0,25+792,81x0,75)x(11x9-900x0,1-9)
Tính bằng cách thuận tiện:
(792,81x0,25+792,81x0,75)x(11x9-900x0,1-9)
ai làm được mình tick
=729x(0,25+0,75)x(11x9-9.10-9)
=729x1x9x(11-10-1)
=729x9x0
=0
(792,81x0,25+792,81x0,75)x(11x9-900x0,1-9)
=792,81x(0,25+0,75)x(999-81)
=792,81x100x918
=79281x918
=72779958
tk minh nha
Tính nhanh
( 792,81x0,25+792,81x0,75 ) x ( 11,9-900x0,1-9 ) =
[792,81 x (0,25 + 0,75)] x (11,9 - 90-9)
=792,81 x -87,1
=-69053,751
Bài 1.Tính bằng cách thuận tiện nhất.
a(792,81x025+792,81x0,75)x(11x9-900x0,1-9).
b.3,54x73+0,23x25+3,54x27+0,17x25.
Giải
a) ( 792,81.0,25 + 792,81.0,75 ).( 11.9 - 900.0,1 - 9 )
= ( 792,81.0,25 + 792,81.0,75 ).9.(11 - 100.0,1 - 1 )
= ( 792,81.0,25 + 792,81.0,75 ).9.0
= 0
b) 3,54.73 + 0,23.25 + 3,54.27 + 0,17.25
= ( 3,54.73 + 3,54.27 ) + ( 0,23.25 + 0,17.25 )
= 3,54.( 73 + 27 ) + 25.( 0,23 + 0,17 )
= 3,54.100 + 25.0,4
= 354 + 10
= 364
(729,81x25%+729,81x3/4)x(11x9-900x0,1-9)
tính giá trị biểu thức
[2012x0,25+2012x0,75]x[11x9-900x0,1-9]
\(=\left(2012x\frac{1}{4}+2012x\frac{3}{4}\right)x\left(11x9-90-9\right)\)
\(=2012x\left(\frac{1}{4}+\frac{3}{4}\right)x\left(11x9-10x9-9x1\right)\)
\(=2012x9x\left(11-10-1\right)\)
=\(2012x9x0\)
=0
Chúc bn học giỏi, k cho mình nhé!!!
= (2012 x 0,25 + 2012 x 0,75) x (99 - 90 - 9 )
= (2012 x 0,25 + 2012 x 0,75) x ( 9 - 9)
=(2012 x 0,25 + 2012 x 0,75) x 0
= 0
(3721x1,3+3570:35)x(11x9-900x0,1-9)
(3721 x 1,3 + 3570 : 35) x (11 x 9 - 900 x 0,1 - 9)
= (3721 x 1,3 + 3570 : 35) x ( 99 - 90 - 9)
= ( 3721 x 1,3 + 3570 : 35) x 0
= 0
(3721X1,3+3570:35)X(11X9-900X0,1-9)=(4837,3+102)X(99-90-9)
=> Vế trước nhân 0 vậy kết quả bằng 0
(123x 0,25+ 123x 0,75)x ( 11x9- 900x0,1 -9)
ét ô ét cíu mik mng ơi~ Ai đúng mik tick cho nhe~~
\(\left(123\text{ ×}0,25+123\text{ ×}0,75\right)\text{ ×}\left(11\text{ ×}9-900\text{ ×}0,1-9\right)\)
\(=\left(123\text{×}0,25+123\text{×}0,75\right)\text{ ×}\left(11\text{×}9-9\text{×}100\text{×}0,1-9\text{×}1\right)\)
\(=\left(123\text{×}0,25+123\text{×}0,75\right)\text{ ×}\left(11\text{×}9-9\text{×}10-9\text{×}1\right)\)
\(=\left[123\left(0,25+0,75\right)\right]\text{×}\left[9\text{×}\left(11-10-1\right)\right]\)
\(=\left(123\text{×}1\right)\text{×}\left(9\text{×}0\right)=123\text{×}0=0\)
1.tính nhanh a) 0,125+21,075+88,36+9,875+78,925+11,6 b) 3457-27x48-48x73+6543 c) (792,81x0,25+792,81x0,75)x(11x9-900x0,1-9) d) (1997x1998x1999x1996x1998)x(1+\(\frac{1}{2}\) :1\(\frac{1}{2}\) -1\(\frac{1}{3}\) )
a) =(0,125+9,875)+(21,075+78,925)+(88,36+11,6)
=10+100+99,96=209,96
b) =792,81.(0,25+0,75).(99-90-9)
=792,81.0=0
c) (1997.1998.1999.1996.1998).(1+1/2:3/2-4/3)
=(1997.1998.1999.1996.1998).(1+1/3-4/3)
=(1997.1998.1999.1996.1998).0
=0
tính nhanh:
(11x9-100+1)x(1x2x3x4x5x6x7x8x9x10)
\(\text{(11x9-100+1)x(1x2x3x4x5x6x7x8x9x10) =(99-100+1)x(1x2x3x4x5x6x7x8x9x10) =0x(1x2x3x4x5x6x7x8x9x10) =0}\)
(11x9-100+1)x(1x2x3x4x...x9x10)
=( 99 - 100 +1) x1x2x3x4x...x9x10
=(99-99) x1x2x3x...x9x10
=0x1x2x3x...x9x10
=0
Chúc bạn học tốt!
\(\left(11\times9-100+1\right)\times\left(1\times2\times3\times4\times5\times6\times7\times8\times9\times10\right)\)
\(=\)\(\left(99-100+1\right)\times\left(1\times2\times3\times4\times5\times6\times7\times8\times9\times10\right)\)
\(=\)\(\left(-1+1\right)\times\left(1\times2\times3\times4\times5\times6\times7\times8\times9\times10\right)\)
\(=\)\(0\times\left(1\times2\times3\times4\times5\times6\times7\times8\times9\times10\right)\)
\(=\)\(0\)