Tính nhanh:
2) -38 . ( 25 - 4) + 25 . ( -4 + 38)
Tính nhanh :
3 . 25 . 8 + 4 . 37 . 6 + 2 . 38 . 12
\(3.25.8+4.37.6+2.38.12\\ =\left(3.8\right).25+\left(4.6\right).37+\left(2.12\right).38\\ =24.25+24.37+24.38\\ =24\left(25+37+38\right)\\ =24.100\\ =2400\)
Tính nhanh:
a,17.(-183)+17.83
b,(-27).145+27.45
c,-38.(25-4)+25.(-4+38)
d,23.(145-17)-145.(23-37)
a) 17.(-183)+17.83
= 17.(-183+83)
= 17.100=1700
b) (-27).145+27.45
= 27.(-145)+27.45
= 27.(-145+45)
= 27.100=2700
c) -38.(25-4)+25.(-4+38)
= -38.25-(-38).4+25.(-4)+25.38
= -38.25+25.38+38.4+25.(-4)
= 0+38.4+(-25).4
= 4.(-25+38)
= 4.13=52
d) 23.(145-17)-145.(23-37)
= (23.145-23.17)-(145.23+145.37)
= [23.(145-17)]-[145.(23+37)]
= (23.128)-(145.60)
= 2944-8700=-5756
Tính nhanh :38×4×60×25×20
38 x 4 x 60 x 25 x 20
= 4560000
k mình nha
38 * 4 * 60 * 25 * 20
= 38 * ( 60 * 20 ) * ( 4 * 25 )
= 38 * 1200 * 100
= 45600 * 100
= 4560000
Tính nhanh
3 . 25 . 8 + 4 . 37 . 6 + 2 . 38 . 12
Ai nhanh mk tick
\(3\cdot25\cdot8+4\cdot37\cdot6+2\cdot38\cdot12\)
\(=24\cdot25+24\cdot37+24\cdot38\)
\(=24\left(25+37+38\right)=24\cdot100=2400\)
Tính nhanh
3 . 25 . 8 + 4 . 37 . 6 + 2 . 38 . 12=2400
3.25.8+4.37.6+2.38.12
=24.25+24.37+24.38
=24(25+37+38)
=24.100
=2400
tính nhanh : a) - 4 . 2 . 6 . 25 . ( - 7 ) . 5
b ) 16 . ( 38 - 2 ) - 38 ( 16 - 1 )
c ) ( - 41 ) : ( 59 + ) + 59 ( 41 - 2 )
Help <# tối nộp rôi
a) -4.2.6.25.(-7).5
= (2.5).(-4.25).(-7.6)
= 10.(-100).(-42)
= 42000
b) 16.(38 - 2) - 38.(16 - 1)
= 16.38 - 16.2 - 38.16 - 38
= -38 - 38
= -38.2
= -76.
c) Câu này đề không rõ nha.
Tính nhanh :
a, 29+132+237+868+763
b, 35 * 34 + 35 * 38 + 65 * 75 +45
c, 3 * 25 *8 +4*37*6 +2*38*12
a) 29 + 132 + 237 + 868 + 763
= ( 132 + 868 ) + ( 237 + 763 ) + 29
= 1000 + 1000 + 29
= 1000 x 2 + 29
= 2000 + 29
= 2029
b) 35 x 34 + 35 x 38 + 65 x 75 + 45
= 35 x ( 34 + 38 ) + 65 x 75 + 45
= 35 x 72 + 65 x 75 + 45
= 2520 + 4875 + 45
= 2520 + 4920
= 7440
c) 3 x 25 x 8 + 4 x 37 x 6 + 2 x 38 x 12
= ( 3 x 8 ) x 25 + ( 4 x 6 ) x 37 + ( 2 x 12 ) x 38
= 24 x 25 + 24 x 37 + 24 x 38
= 24 x ( 25 + 37 + 38 )
= 24 x 100
= 2400
a)29+132+237+868+763
=(132+868)+(237+763)+29
= 1000 + 1000 +29
= 2029
a,29+132+237+868+763
=29+(132+868)+(237+763)
=29+1000+1000
=2029
tính nhanh:
3 x 25 x 8 + 4 x 37 x 6 + 2 x 38 x 12
3 x 25 x 8 + 4 x 37 x 6 + 2 x 38 x 12
= (3.8).25 + (4.6).37 + (2.12).38
= 24.25 + 24.37 + 24.38
= 24. ( 25+37+38)
= 24.100
= 2400
\(3.25.8+4.37.6+2.38.12\)
\(=24.25+24.37+24.38\)
\(=24.\left(25+37+38\right)\)
\(=24.100\)
\(=2400\)
Tham khảo nhé~
3 x 25 x 8 + 4 x 37 x 6 + 2 x 38 x 12
=(3.8).25+(4.6).37+(2.12).38
=24.25+24.37+24.38
=24.(25+27+38)
=24.100
=2400
Tính nhanh :
a , 34 + 35 + ..... + 78 + 79
b , 3 . 25 . 8 + 4 . 6 . 37 + 2 . 38 . 12
a) 34+35+...+78+79
So so hang cua day tren la:
(79-34):1+1=46( so )
Tong cua day tren la:
(79+34)x46:2=2599
DS:2599
Câu a bạn @Conan làm rồi
mik làm câu b
\(\text{= 24.25 + 24.37 + 24.38 = 24.(25+37+38) = 24.100 = 2400}\)
giải thích r ạ
b, 23.(145 - 17) - 145. (23 - 6)
= 145.23 - 17.23 - 145.23 + 145.6
= (145.23 + 145.6) - (145.23 + 17.23)
= 145.(23 + 6) - 23.(145 + 17)
= 145.29 - 23.162
= 479
c, -38. (25 - 4) + 25. (-4 + 38)
= (-38).25 - 4.(-38) + 25. (-4) + 25.38
= [(-38).25 - 4.(-38)] + [25. (-4) + 25.38]
= (-38).(25 - 4) + 25. [(-4) + 38]
= (-38). 21 + 25.34
= - 798 + 850
= 52