15-6=?
12+5=?
16-3=?
26+3=?
36-24=?
Bai 3: Ti'nh cac tong sau mot cach hop li
1) (-37) + 14 + 26 + 37
2) (-24) + 6 + 10 + 24
3) 15 + 23 + (-25) + (-23)
4) 60 + 33 + (-50) + (-33)
5) (-12) + (-13) + 36 + (-11)
6) (-16) + 24 + 16 - 34
7) (-16) + (-209) + (-14) + 209
8) 25 + 37 - 48 - 25 - 37
9) 2575 + 37 - 2576 - 29
10) 34 + 35 + 36 + 37 - 14 - 15 - 16 - 17
11) 4573 + 46 - 4573 + 35 - 16 - 5
12) 32 + 34 + 36 + 38 - 10 - 12 - 14 - 16 - 18
Giup mk voi
Viết mỗi tập hợp sau bằng cách chỉ rõ tính chất đặc trưng cho các phần tử của nó:
A = {0; 2; 5}
B = {3; 9; 27; 81}
C = {4; 16; 36; 64; 100}
D = {9, 36, 81; 144}
E = {0; 4; 8; 12; 16}
G = {- 3; 9; - 27; 81}
K = {2/3; 3/8; 4/15; 5/24; 6/35}
H = {8; 14; 20; 26}
L = {- 2; 3; 5}
B={x\(\in\)N|x=3k; 1<=k<=4}
C={x\(\in\)N|x=4*a2; 1<=a<=5}
D={x\(\in\)N|x=9*a2;1<=a<=4}
E={x\(\in\)N|x=4k; 0<=x<=4}
G={x\(\in\)N|x=(-3)^k; 1<=k<=4}
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37=
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37
=(1+37)x37:2
=703
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+149+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39*100
a) 2×24×25+3×41×16+6×2×8×17
b)15×360+15×2×27+1500
c)47×63+53×21+47×37+53
d)2×169×12-3×68×8-24
e)2×56×24-3×36×16+4×12×95-6×3×8×5
f)(36×15×169)÷(5×18×13)
h)(112+2×28-5×28)÷28
i)1448-(448+500)
tính hợp lí
1/ (-37)+14+26+37
2/ (-24)+6+10+24
3/ 15+23+(-25)+(-23)
4/ 60+33+(-50)+(-33)
5/ (-16)+(-209)+(-14)+209
6/ (-12)+(-13)+36+(-11)
7/ -16+24+16-34
8/ 25+37-48-25-37
9/ 2575+37-2576-29
10/ 34+35+36+37-14-15-16-17 ( làm đc 1 like bài dễ mè) mik đăng cho nó vui
1) (-37) + 14 + 26 + 37
= (-37 + 37) + 14 + 26
= 0 + 40
= 40
2) (-24) + 6 + 10 + 24
= (-24 + 24) + 6 + 10
= 0 + 16
= 16
3) 15 + 23 + (-25) + (-23)
= 15 + (-25) + (-23 + 23)
= -10 + 0
= -10
4) 60 + 33 + (-50) + (-33)
= 60 + (-50) + (-33 + 33)
= 10 + 0
= 10
Tính hợp lí
(-37) + 14 + 26 + 37
(-24) + 6 + 10 + 24
15 + 23 + (-25) + (-23)
60 + 33 + (-50) + (-33)
(-16) + (-209) + (-14) + 209
(-12) + (-13) + 36 + (-11)
-16 + 24 + 16 – 34
25 + 37 – 48 – 25 – 37
2575 + 37 – 2576 – 29
34 + 35 + 36 + 37 – 14 – 15 – 16 – 17
Câu a:
Ta thấy 37 - 37 = 0
nên nhóm lại kết quả là 14 + 26 = 40
Câu b:
tương tự, kết quả là 6 + 10 = 16
Các câu còn lại như vậy
( -37)+14 +26 +37
=( -37 )+ 37 + (14 + 26 )
=0 +40 = 40
- 24 + 6 +10 +24
=( -24 ) + 24 +( 6 + 10 )
=0 + 16 = 16
15 + 23 + (-25 ) + ( -23 )
= 15 + ( -25 ) + 23 +( -23 )
= -10 + 0
= - 10
60 + 33 + ( -50 ) + ( 33 )
= 60 + (- 50 ) + 33 + ( -33)
= 10 + 0 = 10
( -16) +(-209) + ( -14 ) + 2009
= ( -16 ) + ( -14 ) + ( -209 ) + 209
= -30 + 0
= -30
( -12 ) + ( -13 ) + 36 + (- 11 )
= ( -12 ) + (- 13 ) + ( -11 ) + 36
= - 25 + ( - 11 ) + 36
= -36 + 36
= 0
Bài 1Tinh1 hợp lí
1) 2575 + 37 - 2576 -29
2) 35 + 35 + 36 +37 - 14 -15 -16 -17
3) 13. (-12) +87 .(-12)
4) 26 .17+17 .74
5) 25 . (-18) + 25 (- 82)
6) 25+37- 48 - 25 - 37
7) (-16) + 24 + 16 - 34
\(2575+37-2576-29\)
\(=2612-2576-29\)
\(=36-29=7\)'
\(35+35+36+37-14-15-16-17\)
\(=70+\left(36-16\right)+\left(37-17\right)-14-15\)
\(=70+20+20-14-15\)
\(=90+6-15\)
\(=96-15=81\)
\(13\cdot\left(-12\right)+87.\left(-12\right)\)
\(=\left(-12\right)\cdot\left(13+87\right)\)
\(=\left(-12\right)\cdot100=-1200\)
\(26\cdot17+17\cdot74\)
\(=\left(26+74\right)\cdot17\)
\(=100\cdot17=1700\)
\(25\cdot\left(-18\right)+25\left(-82\right)\)
\(=25\cdot\left[\left(-18\right)+\left(-82\right)\right]\)
\(=25\cdot\left(-100\right)=\left(-2500\right)\)
\(25+37-48-25-37\)
\(=\left(25-25\right)+\left(37-37\right)-48\)
\(=0+0-48\)
\(=0-48=\left(-48\right)\)
\(\left(-16\right)+24+16-34\)
\(=\left[\left(-16\right)+16\right]+\left(24-34\right)\)
\(=0+\left(-10\right)=\left(-10\right)\)
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50=?
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50=1275