Thực hiện phép tính:
-75+(-49)+|-75|+49-12
3. Thực hiện phép tính: A, 61• 45 + 61 • 23 - 68 • 51 B, 3 • 52 - ( 75 - 4 • 23 ) C,36 : { 22 • 5 - [ 30 - ( 5 - 1 ]2 } D,(12•49 -3 • 22•72):(2020• 2021)
a: \(61\cdot45+61\cdot23-68\cdot51\)
\(=61\left(45+23\right)-68\cdot51\)
\(=68\cdot61-68\cdot51\)
\(=68\left(61-51\right)=68\cdot10=680\)
b: \(3\cdot5^2-\left(75-4\cdot2^3\right)\)
\(=75-75+4\cdot8\)
\(=4\cdot8=32\)
c: \(36:\left\{2^2\cdot5-\left[30-\left(5-1\right)^2\right]\right\}\)
\(=\dfrac{36}{20-30+4^2}\)
\(=\dfrac{36}{-10+16}=\dfrac{36}{6}=6\)
d: \(\left(12\cdot49-3\cdot2^2\cdot7^2\right):\left(2020\cdot2021\right)\)
\(=\dfrac{\left(12\cdot49-12\cdot49\right)}{2020\cdot2021}=0\)
bài 5 Thực hiện phép tính -tính nhẩm nếu có thể:
a(317+49)-117=
b867-(167+80)=
c(125.7):25=
d3000:75=
a) (317+49)-117
=366-117
=249
b)867-(167+80)
=867-247
=620
c)(125.7):25
=875:25
=35
d)3000:75=40
TL :
\(\left(317+49\right)-117=249\)
\(867-\left(167+80\right)=620\)
\(\left(125.7\right):25=35\)
\(3000:75=40\)
Hok tốt
1. Thực Hiện Phép Tính
a.1/-4-4/-3+1/-3(50%-1 2/3
b.-1,4x15/-49-(2/5+4/3): 2 3/5
c.75%-1 1/2 +0,5 /5/12
d.0,7x2 2/3x20x0,375x5/28
2.Tính Nhanh
a.A=12,87-14,7+14,13-37,3
b.B=-4/12+18/45+-6/9+-21/35+6/30
Bài 2:
a: A=(12,87+14,13)+(-14,7-37,3)
=27-52=-25
b: B=-1/3+2/5-2/3-3/5+1/5
=-1
Thực hiện phép tính
a ) 17 + 25 .4 - 33
b ) 12 . 53 - 162 : 32
c ) 2347 - [ 75 - ( 9 - 4 )2 ]
d ) 1672 + [ 49 + ( 13 - 7 )3 ]
Thực hiện phép tính:
a. \(\sqrt{25}+2\sqrt{49}\)
b. \(\sqrt{16}.\sqrt{25}+\sqrt{169}:\sqrt{49}\)
c. \(\sqrt{\left(3-\sqrt{7}\right)^2}+\sqrt{7}\)
d. \(2\sqrt{3}-\sqrt{75}+2\sqrt{12}\)
Ta có: \(\sqrt{75}-2\cdot\sqrt{12}+\sqrt{3}\)
\(=5\sqrt{3}-2\cdot2\sqrt{3}+\sqrt{3}\)
\(=6\sqrt{3}-4\sqrt{3}\)
\(=2\sqrt{3}\)
Thực hiện phép tính: 5 7 − 7 5 − 1 2 − − 2 7 − 1 10
5 7 − 7 5 − 1 2 − − 2 7 − 1 10 = − 24 35 − 1 2 − − 27 70 = − 24 35 − 31 35 = − 11 7
giúp mk với
-75+(-49)+|75|+49-12
-75+(-49)+|75|+49-12
= -75-49+75+49-12
= (-75+75) +( -49+49) -12
= 0+0+(-12)
=-12
thực hiện phép tính
a)250:75-[150-(23-13)2]
b)2347-[75-(9-4)2]
c)2.(5.42-18)
d)1672+-[49+(13-7)3]
e)321-21.[(2.33+44:32)-52]
g)80-[130-(12-4)2]
h)426-{3[152-(5-2)2]+1}:10
tính hộ mình với
a) 100:{250:[450−(4.53−25.4)]}100:{250:[450−(4.53−25.4)]}
=100:{250:[450−(4.125−25.4)]}=100:{250:[450−(4.125−25.4)]}
=100:{250:[450−(500−100)]}=100:{250:[450−(500−100)]}
=100:[250:(450−400)]=100:[250:(450−400)]
=100:(250:50)=100:(250:50)
=100:5=100:5
=20=20
b) 4(18−15)−(5−3).324(18−15)−(5−3).32
=4.3−2.32=4.3−2.32
=4.3−2.9=4.3−2.9
=12−18=12−18
=−6=−6