Tóm tắt Bài Giải

a) 35.34+35.36+65.75+65.45

Giả sử dấu "." là phép nhân (sử dụng tính chất phân phối):​=35×(34+36)+65×(75+45)=35×70+65×120=2450+7800=10250​

b) 53.(51+4).(49+91)+53

Sử dụng tính chất phân phối và tính toán trong ngoặc:

=53×55×140+53=53×7700+53×1=53×(7700+1)=53×7701=408153​

a136,35

B = \(\frac{2^{10}.13+2^{10}.65}{2^8.104}=\frac{2^{10}.\left(13+65\right)}{2^8.104}=\frac{2^{10}.78}{2^8.104}\)

B = \(\frac{2^2.39}{52}=\frac{2^2.39}{2^2.13}\)

B = \(\frac{39}{13}\)

B = 3

B = \(\frac{2^{10}.13-2^{10}.65}{2^8.104}=\frac{2^{10}.\left(13+65\right)}{2^{8.104}}=\frac{2^{10}.78}{2^8.104}=\frac{2^2.39}{52}=\frac{2^2.39}{2^2.13}=\frac{39}{13}=3\)

a, 35.34 + 35.86 + 65.75 + 65.45

= 35.(34 + 86) + 65.(75 + 45)

= 35.120 + 65.120

= 120.(35+65)

= 120.100

= 12000

b, \(7.5^2-32:2^3+9\)

= 7.25 - 32:8 + 9

= 175 - 4 + 9

= 180

a) 35.34 + 35.86 + 65.75 + 65.45 =

( 35 + 65 ) x ( 34 + 86 ) + ( 75 + 45 )

100 x 120 x 120

100 x 14400

1440000

\(35\cdot34+35\cdot86+65\cdot75+65\cdot45\\ =35\cdot\left(34+86\right)+65\cdot\left(75+45\right)\\ =35\cdot120+65\cdot120\\ =120\cdot\left(35+65\right)\\ =120\cdot100\\ =12000\)

= 35.(34+56+75+45) 

= 35. 210

= 7350

hình như sai rồi, bạn đọc kĩ đề đi =)

\(\frac{2^{10}.13+2^{10}.65}{2^8.104}=\frac{2^{10}.13+2^{10}.5.13}{2^8.2^3.13}=\frac{2^{10}.13\left(1+5\right)}{2^{11}.13}=\frac{2^{10}.13.2.3}{2^{11}.13}=\frac{2^{11}.3.13}{2^{11}.13}=3\)

= 3 mk làm rồi chắc chắn 100% luôn

Bài 2:

a)38.63+37.38=38(63+37)=3800

b)12.53+53.172– 53.84=53(12+172-84)=5300

c)35.34+35.38+65.75+65.45=35(34+38)+65(75+45)=2520+7800=10320

d)39.8 +60.2 +21.8=8(39+21)+120=480+120=600

e)36.28+36.82+64.69+64.41=36(28+82)+64(69+41)=3960+7040=11000

a)38.63+37.38

=38.(63+37)

=38.100

=3800

a) \(=38\left(63+37\right)=38.100=3800\)

b) \(=53\left(12+172-84\right)=53.100=5300\)

c) \(=35\left(34+38\right)+65\left(75+45\right)=35.72+65.120=10422\)

d) \(=39.8+15.8+21.8=8\left(39+15+21\right)=8.75=600\)

e) \(=36\left(28+82\right)+64\left(69+41\right)=36.110+64.110=110\left(36+64\right)=110.100=11000\)