Lời giải:
Ta có:
$1+2+3+...+200=\frac{200.201}{2}=20100$
$6+8+10+...+34=\frac{(34+6).15}{2}=300$
Do đó: $B=\frac{20100}{300}=67$
tinh nhanh
a,A=100+98+96+...+2-97-95-...-1
b,B=1+2-3-4+5+6-7-8+9+10-11-12+...-229-330+301+302
c,C=41*66+34*41/3+7+11+...+79
d,D=1+2+3+...+200/6+8+10+...+34
e,E=1*5*6+2*10*12+20*24*4+9*45*54/1*3*5+2*6*10+4*12*20+9*27*45
a )210 - 5 ( x-10)=200
b) [3.(70- x)+5]:2=46
c) 230 +[2^4+(x-5)]=315.2018^0
d)707 : [(2^x -5)+74] = 4^2-3^2
4.24.5^2-(3^3.18+3^3.12)
31.15.7^2.4-31.49.40
1+2+3+4+5+6+7+8+9+10
1+3+5+7+9+11+13+15+19
2+6+10+14+22+23+26+34
5+8+11+14+17+20+23+26+29
1+6+11+16+21+26+31+36+41+47+51
10+13+16+19+22+25+28+31+34+37+40
5+7+9+11+13+15+17+3+8+13+18+23+28
4+7+10+13+16+19+5+9+13+17+21+25
1+2+3+4+5+6+7+8+9+10+11+12+1+1345+6+544+435+22+00+34+567+13+7+6+9+8+0+6+5+4+3+4+5+6+66+6+2+3+8888+666+1000+87+98
AI GIẢI ĐƯỢC THÌ CHO LIKE SUỐT ĐỜI!!!!
tinh bang cach hop ly
Tử số: 1+2+3+...+200
Mẫu số: 6+8+10+..+34
tính bằng cách hợp lý
A=(1+2+3+...+200) : (6+8+10+...+34)
B=( 41x66+34x66):(3+7+11+...+79)
a) 1-2+3-4+5-6+7-8+9-10+11
b)98+87+76+...+21-12-23-34-...-89
1) Thực hiện phép tính
a) 78 - 12.5 + 32
b) 42 . 55 + 2 . 45 . 8 - 20240
c) 1800 : {49 - [ 2.(62 -34)3 - 54 : 53]}
d)\(\dfrac{15.2^{11}.3^{10}-6^{11}}{12.6^{10}+7.4^6.9^6}\)
2) Tìm x biết
27 : 3x + 31 = 2.52 - 42
Giải gấp cho em với ạ
47-[(45.2^4-5^2.12):14]
50-[(20-2^3):2+34]
10^2-[60:(5^6:5^4-3.5)]
50-[(50-2^3.5):2+3]
10-[(8^2-48).5+(2^3.10+8)]:28
8697-[3^7,3^5+2(13-3)]
2011+5[300-(17-7^2)]
695-[200+(11-1^2)]
129-5[29-(6-1^2)]
2010-2000:486-2(7^2-6)]
