Tính nhanh:
a) 246+58+54+242
b)11+12+13+....+17+18+19
c)64.16+81.84+17.16
d)3.25.8+4.37.6+2.38.12
Tính nhanh:
a) 23.56 + 56.77;
b) 32.19 + 32;
c) 35.34 + 35,86 + 65.75 + 65.45;
d) 43.17 + 29.57 + 13.43 + 57;
e) 3.25.8+4.37.6 + 2.38.12
f) 64.16+81.84+17.16
a) 23.56 + 56.77 = (23 + 77).56 = 100.56 = 5600.
b) 32.19 + 32 = 32.(19 +1) = 32.20 = 640.
c) 35.34 + 35.86 + 65.75 + 65.45 = 35.(34 + 86) + 65.(75 + 45)
= 120.35+120.65 -120.(35 + 65) = 12000.
d) 43.17 + 29.57 +13.43 + 57 = 43.(17 +13) + 57.(29 +1)
= 43.30 + 57.30 = 30. (43+57) = 3000.
e) 3.25.8 + 4.37.6 + 2.3812 - 24.25 + 24.37 + 24.38
= 24.(25 + 37 + 38) = 2400.
f) 64.16 + 81.84+17.16 = 16.(64+17)+81.84 = 16.81+81.84
= 81.(16 + 84) = 8100
Tính nhanh:
a) 23.56 + 56.77;
b) 32.19 + 32;
c) 35.34 + 35,86 + 65.75 + 65.45;
d) 43.17 + 29.57 + 13.43 + 57;
e) 3.25.8+4.37.6 + 2.38.12
f) 64.16+81.84+17.16
a) 23.56 + 56.77 = (23 + 77).56 = 100.56 = 5600.
b) 32.19 + 32 = 32.(19 +1) = 32.20 = 640.
c) 35.34 + 35.86 + 65.75 + 65.45 = 35.(34 + 86) + 65.(75 + 45)
= 120.35+120.65 -120.(35 + 65) = 12000.
d) 43.17 + 29.57 +13.43 + 57 = 43.(17 +13) + 57.(29 +1)
= 43.30 + 57.30 = 30. (43+57) = 3000.
e) 3.25.8 + 4.37.6 + 2.3812 - 24.25 + 24.37 + 24.38
= 24.(25 + 37 + 38) = 2400.
f) 64.16 + 81.84+17.16 = 16.(64+17)+81.84 = 16.81+81.84
= 81.(16 + 84) = 8100
a) 274+(158+26) b) 29+132+237+868+163 c) 98.31+62 d) 10+11+12+13+...+99 f) (1+3+5+7+... + 217) (135135.137 - 135.137137 e) 3.25.8+4.37.6+2.38.12
a: =274+184=458
b: =29+132+868+237+163
=1000+400+29
=1429
f: =A*135*137(1001-1001)=0
e: =24*25+24*37+24*38
=24*100=2400
c: =31(98+2)=31*100=3100
Tính nhanh: 3.25.8+4.37.6 + 2.38.12.
3.25.8 + 4.37.6 + 2.3812 - 24.25 + 24.37 + 24.38
= 24.(25 + 37 + 38) = 2400
Tính nhanh:
3.25.8+4.37.6+2.38.12
3*25*8+4*37*6+2*38*12=24*25+24*37+24*38=24*(25+37+38)=24*100=2400
3.25.8+4.6.37+2.38.12
<=> 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 . 3 = 24 . ( 25 + 37 +38 ) = 24 . 100 = 2400
3.25.8+4.37.6+2.38.12
3.25.8+4.37.6+2.38.12
= 2400
HỌC TỐT!
3.25.8+4.37.6+2.38.12 = ?
Trả lời :
3.25.8+4.37.6+2.38.12 = 2400
hok tốt :v
Tính nhanh
3.25.8+4.37.6+2.38.12
3.25.8 + 4.37.6 + 2.38.12
= 3.8.25 + 4.6.37 + 2.12.38
=24.25 + 24.37 + 24.38
=24.(25+27+38)
=24.87
=2088
Tính nhanh
29+132+237+868+736
3.25.8+4.37.6+2.38.12
Biết làm câu b
=24.25+24.37+24.38
=24.(25+24+38)
=24.87
=2088
cau a là
29 + 135 + 234 + 865 + 766
=(135 + 865) + ( 234 + 766) + 29
= 1000 + 1000 + 29
= 2000 + 29
= 2029
câu b
3.25.8 + 4.37.6 + 2.38.12
= 3.8.25 + 4.6.37 + 2.12.38
=24.25 + 24.37 + 24.38
=24.(25+27+38)
=24.87
=2088
a=2029
b=2088
k cho mình nha chúc bạn học tốt