55+25-55+94781-2224 =
55 x 55 =
75 x 65 =
25 x 25 =
35 x 35 =
55 x 55 =3025
75 x 65 =4875
25 x 25 =625
35 x 35 =1225
55 x 55 =3025
75 x 65 = 4875
25 x 25 =625
35 x 35 = 1225
Tính bằng cách thuận tiện (ý là tính nhanh ấy)
55 x 25 - 55 x 20 + 55 x 4 + 55
=55(25-20+4+1)
=55.10
=550
=55(25-20+4+1)
=55
Theo đề ta có:
55 x 25 - 55 x 20 + 55 x 4 + 55
= 55 x 25 - 55 x 20 + 55 x 4 + 55 x 1
= 55 x ( 25 - 20 + 4 + 1 ) ( rút thừa số chung là 55 )
= 55 x 10 = 550
Chúc bạn học tốt, nhớ cho mình đúng nha.
Điền dấu <, >, = thích hợp vào chỗ chấm:
34....38 55...57 90...90
36.. .30 55...55 97...92
37....37 55...51 92...97
25...30 85...95 48...42
34 < 38 55 < 57 90 = 90
36 > 30 55 = 55 97 > 92
37 = 37 55 > 51 92 < 97
25 < 30 85 < 95 48 > 42
13(55-29)-55(13-29)
37(27+25)-27(37+25)
28(-25)+72(-25)
tính nhanh
a: \(=13\cdot55-13\cdot29-55\cdot13+55\cdot29\)
\(=-13\cdot29+55\cdot29=29\cdot42=1218\)
b: \(=37\cdot27+37\cdot25-27\cdot37-27\cdot25\)
\(=27\cdot12=324\)
c: \(=-25\left(28+72\right)=-25\cdot100=-2500\)
Tính nhanh:
a, 25 x 9101 x 4
b, 99 x 55 + 55
a, 25 x 9101 x 4 = (25 x 4) x 9101 = 100 x 9101 = 910100
b, 99 x 55 + 55 = 55 x ( 99 + 1) = 55 x 100 = 5500
a,25x9101x4=9101x(25x4)=9101x100=910100
b,99x55+55=55x(99+1)=55x100=5500
a) (-10).35+10.(-12)-(-10)
b)20.(-345)+(-20).(-315)
c)25.(27-55)-27.(25-55)
d)25.(-415)+9(-15).418
e)5+(-8).3
MÌNH ĐANG CẦN GẤP NHA
a: \(\left(-10\right)\cdot35+10\cdot\left(-12\right)-\left(-10\right)\)
\(=\left(-10\right)\cdot35+\left(-10\right)\cdot12-\left(-10\right)\)
\(=-10\left(35+12-1\right)=-10\cdot46=-460\)
b: \(20\cdot\left(-345\right)+\left(-20\right)\cdot\left(-315\right)\)
\(=20\cdot\left(-345\right)+20\cdot315\)
\(=20\left(-345+315\right)=-30\cdot20=-600\)
c: \(25\left(27-55\right)-27\left(25-55\right)\)
\(=25\cdot27-25\cdot55-27\cdot25+27\cdot55\)
\(=27\cdot55-25\cdot55=2\cdot55=110\)
d: \(25\cdot\left(-415\right)+9\cdot\left(-15\right)\cdot418\)
\(=-25\cdot415-9\cdot15\cdot418\)
\(=-5\left(5\cdot415+3\cdot9\cdot418\right)\)
\(=-5\left(2075+11286\right)=-5\cdot13361=-66805\)
e: \(5+\left(-8\right)\cdot3\)
=5-24
=-19
a) 5/9 * 12/25
b) 12/11 : 36/55
c) 9/55 * 22
d) 144/7 : 36
a) 5/9 x 12/25 = 4/15
b) 12/11 : 36/55 = 5/3
c) 9/55 x 22 = 18/5
d) 144/7 : 36 = 4/7
a) 5/9 x 12/25 = 4/15
b) 12/11 : 36/55 = 5/3
c) 9/55 x 22 = 18/5
d) 144/7 : 36 = 4/7
a) 5/9 x 12/25 = 4/15
b) 12/11 : 36/55 = 5/3
c) 9/55 x 22 = 18/5
d) 144/7 : 36 = 4/7
Tính:
18 + 16 + 14 + 35 + 110 + 160 + 150 + 145+ 158 + 140 + 55 + 25 = …
110 + 160 + 150 + 145+ 158 + 140 = …
55 + 25 + 18 + 16 + 14 + 35 = …
Tính nhanh:
A) 1+2+3+...+87
B)2+4+6+...54
C)3+6+9+...+99
D)45*25+45*75+55*25*25+55*75
NHANH NHA GIÚP MÌNH!!!!!!!!!!!!!
a, 1 + 2 + 3 + ... + 87
= (1 + 87).87 : 2
= 87.88 : 2
= 87.44
= 3828
b, 2 + 4 + 6 + ... + 54
= (2 + 54).27 : 2
= 27.56 : 2
= 27.28
= 756
c, 3 + 6 + 9 + ... + 99
= (99 + 3).49 : 2
= 49.102 : 2
= 49.51
= 2499
d, 45.25 + 45.75 + 55.25.25 + 55.75
= 45. (25 + 75) + 55(25.25 + 75)
= 45.100 + 55.700
= 4500 + 38500
= 43000
\(d,45x25+45x75+55x25+55x75\)
\(=45x\left(25+75\right)+55x\left(25+75\right)\)
\(=45x100+55x100\)
\(=100x\left(45+55\right)\)
\(=100x100\)
\(=10000\)