tính
a,100-[116-(13-52)]
Tính bằng cách thuận tiện nhất : 30/13 x 52/29 x 116/240
\(\frac{30}{13}\)× \(\frac{52}{29}\)×\(\frac{116}{240}\)= \(\frac{3×10×13×4×29×4}{13×29×2×3×4×10}\)( gạch số giống nhau đi )=\(\frac{4}{2}\)= 2
a) A= 100 - 116 : 4
b) B= 100 - [ 116 - (13 - 5)2]
c) C= |- 65| + (- 42) + |65|
a) A= 100 - 116 : 4
=100-29
=71
b) B= 100 - [ 116 - (13 - 5)2]
=100-[116-82]
=100-(116-64)
=100-52
=48
c) C= |- 65| + (- 42) + |65|
= 65+(-42)+65
= 88
a) A = 100 - 116 : 4
A = 100 - 29
A = 71
Vậy A = 71
b) B = 100 - [ 116 - ( 13 - 5 )2 ]
B = 100 - [ 116 - 82 ]
B = 100 - [ 116 - 64 ]
B = 100 - 52
B = 48
Vậy B = 48
c) C = | - 65 | + ( - 42 ) + | 65 |
C = 65 + ( - 42 ) + 65
C = ( 65 + 65 ) + ( - 42 )
C = 130 + ( - 42 )
C = 130 - 42
C = 88
Bài 1:So Sánh(nhanh nhất)
\(\dfrac{-13}{38}va\dfrac{29}{-88},\dfrac{-18}{31}va\dfrac{-1818}{3131}\)
Bài 2:Tính
a)\(\dfrac{-1}{39}+\dfrac{-1}{52}\)
b)\(\dfrac{-6}{9}+\dfrac{-12}{16}\)
Bài 1:
\(\dfrac{-13}{38}\) và \(\dfrac{29}{-88}\)
\(\dfrac{-13}{38}=\dfrac{-13.29}{38.29}=\dfrac{-377}{1102}\)
\(\dfrac{29}{-88}=\dfrac{-29}{88}=\dfrac{-29.13}{88.13}=\dfrac{-377}{1144}\)
Vì \(\dfrac{-377}{1102}< \dfrac{-377}{1144}\) nên \(\dfrac{-13}{38}< \dfrac{29}{-88}\)
\(\dfrac{-18}{31}\) và \(\dfrac{-1818}{3131}\)
\(\dfrac{-18}{31}\)
\(\dfrac{-1818}{3131}=\dfrac{-1818:101}{3131:101}=\dfrac{-18}{31}\)
Vì \(\dfrac{-18}{31}=\dfrac{-18}{31}\) nên \(\dfrac{-18}{31}=\dfrac{-1818}{3131}\)
Bài 2:
a) \(\dfrac{-1}{39}+\dfrac{-1}{52}=\dfrac{-4}{156}+\dfrac{-3}{156}=\dfrac{-4+-3}{156}=\dfrac{-7}{156}\)
b) \(\dfrac{-6}{9}+\dfrac{-12}{16}=\dfrac{-2}{3}+\dfrac{-3}{4}=\dfrac{-8}{12}+\dfrac{-9}{12}=\dfrac{-17}{12}\)
13.16+13.(-116)+17.(-100
\(13\cdot16+13\cdot\left(-116\right)+17\cdot\left(-100\right)\)
\(=13\left(16+-116\right)+17\cdot\left(-100\right)\)
\(=13\cdot\left(-100\right)+17\cdot\left(-100\right)\)
\(=\left(-100\right)\cdot\left(13+17\right)=30\cdot\left(-100\right)=-3000\)
13.16+13.(-116)+17.(-100)
=13.(-116+16)+17.(-100)
=13.(-100)+17.(-100)
=(-100).(13+17)
=-100.30
=(-3000)
quy đồng mẫu số rồi tính
a. 10/13 + 9/16 7/90 + 123/270
b. 19/21 - 5/12 90/100 - 25/40
a. 10/13 + 9/16
=160/208+117/208
=277/208
7/90 + 123/270
=7/90+41/90
=48/90
=8/15
b. 19/21 - 5/12
=76/84-35/84
=41/84
90/100 - 25/40
=9/10-25/40
=36/40-25/40
=11/40
a. 10/13 + 9/16
=160/208+117/208
=277/208
7/90 + 123/270
=7/90+41/90
=48/90
=8/15
b. 19/21 - 5/12
=76/84-35/84
=41/84
90/100 - 25/40
=9/10-25/40
=36/40-25/40
=11/40
a) \(\dfrac{10}{13}+\dfrac{9}{16}\) \(\dfrac{7}{90}+\dfrac{123}{270}\)
= \(\dfrac{160}{208}+\dfrac{117}{208}\) = \(\dfrac{7}{90}+\dfrac{41}{90}\)
= \(\dfrac{277}{208}\) = \(\dfrac{8}{15}\)
b) \(\dfrac{19}{21}-\dfrac{5}{12}\) \(\dfrac{90}{100}-\dfrac{25}{40}\)
= \(\dfrac{76}{84}-\dfrac{35}{84}\) = \(\dfrac{9}{10}-\dfrac{25}{40}\)
= \(\dfrac{41}{84}\) = \(\dfrac{36}{40}-\dfrac{25}{40}\)
= \(\dfrac{11}{40}\)
Hok tốt
100-[116-(13-52)]
\(100-\left(116-\left(13-5^2\right)\right)=100-\left(116-\left(-12\right)\right)\)
\(=100-\left(116+12\right)=100-128=-28\)
100-[116-(13-52)]
=100-[116-(13-25)]
=100-(116-13+25)
=100-(103+25)
=100-128
=-28
100-[116-(13-5)2]
\(100-\left[116-\left(13-5\right)^2\right]\)
\(=100-\left(116-8^2\right)\)
\(=100-\left(116-64\right)\)
\(=100-52\)
\(=48\)
=100-(116-(9.9)
=100-(116-81)
=100-35=65
Tính
a) 25; b) 33; c) 52; d) 109.
a) 25 = 2.2.2.2.2 = 32
b) 33 = 3.3.3 = 27
c) 52 = 5.5 =25
d) 109 =10.10.10.10.10.10.10.10.10 = 1 000 000 000
Bài 1: Thực hiện phép tính
a) 22.32- 5.2.3= b) 3.52+15.22 -12.3 = c) 52.2+20:22= d) 53:52+22.3= e) 72.15-5.72= f) 43.125-125:52 =
a: =6^2-15*2
=36-30=6
b: =3*25+15*4-3
=72+60
=132
c: =25*2+5
=50+5
=55
d: =5+12=17
e: =7^2(15-5)=49*10=490
f: =4^3*125-125:25
=1000-5
=995
Câu 1: Tính
a, ( -14 ) + 5 + 17 + 14
b, 40 + 13 + ( -25 ) + ( -13 )
c, ( -5 ) + ( -146 ) + ( -15 ) + 14
d, ( -2 ) + ( -5 ) + 20 + ( -13 )
Câu 2: Tính
a, ( 123 - 37 ) - 123
b, ( -224 ) - ( 34 - 224 )
c, 126 - ( 126 - 33 )
d, ( -53 23 ) - ( 567 - 53 )
Câu 1:
a:=17+5=22
b: =40-25=15