1/6 + 4/21 + 1/56 + 9/136 + 8/425 + 12/925 kết quả là bao nhiêu
1/6 + 4/21 + 1/56 + 9/136 + 8/425 + 12/925 = 35/74.
1/6 + 4/21 + 1/56 + 9/136 + 8/425 + 12/925
= 1/2.3 + 4/3.7+ 1/7.8+9/8.17+1/17.25+12/25.37
=1/2-1/3+1/3-1/4+1/7-1/8+1/8-1/17+1/17-1/25+`1/25-1/37
=1/2-1/37
=35/74
h)
(9-x)+(13-x)+(17-x)+(21-x)+(25-x)+...+(85-x)=925
làm xong trước 6h30phút
(9+13+17+...+85)-(x+x+x+...+x)=925
bn tự làm tiếp nha
=( 9 + 13 +....+85 ) - ( x + x +.....+ x) =925
=940 - x.20 = 925
x.20 = 940-925
x.20 = 15
x = 15:20
x = 0.75
Tính
a) 4 9 + 5 9 b) 6 - 9 5
c) 6 7 × 5 2 d) 9 25 : 9 25
Tính giá trị biểu thức:
a) (21,34+232)+23,54
b) 23,4+23,5+23,6+23,7+...+34,1
c)925-93+9,45-6,75+4,5
d) (23,45+34,56+45,67+56,78)x12,5x12
làm xong nhớ kết bạn nhé
Làm phép tính :
a) ( 523. 518 ) : 539 - 50 . 05
b)[2.3mũ 3 + 144: (7mũ 2 - 925: 5 mũ 2 )]. gttđ của -8
a)\(\left(5^{23}.5^{18}\right):5^{39}-5^0.0^5\)
= \(5^{41}:5^{39}-1.0\)
= \(5^2-0\)
= \(25-0=25\)
b)\(\left[2.3^3+144:\left(7^2-925:5^2\right)\right].\left|-8\right|\)
= \(\left[2.27+144:\left(49-925:25\right)\right].8\)
= \(\left[54+144:\left(49-37\right)\right].8\)
= \(\left[54+144:12\right].8\)
= \(\left[54+12\right].8\)
= \(66.8\)
= 528
1. 5/21+0,5-19/23+16/21-4/23
2. 27/23+5/21-4/23+6/21+1/2
giải giúp mình nhé mấy bạn
1, \(\frac{5}{21}+0,5-\frac{19}{23}+\frac{16}{21}-\frac{4}{23}\)
\(=\frac{5+16}{21}-\frac{19+4}{23}+0,5\)
\(=1-1+0,5\)
\(=0,5\)
2,\(\frac{27}{23}+\frac{5}{21}-\frac{4}{23}+\frac{6}{21}+\frac{1}{2}\)
\(=\frac{27-4}{23}+\frac{5+6}{21}+\frac{1}{2}\)
\(=1+\frac{11}{21}+\frac{1}{2}\)
\(=\frac{42+22+21}{42}\)
\(=\frac{85}{42}\)
=16/21 + 4/23 + 5/21 - 4/23 - 5/21
\(\dfrac{16}{21}+\dfrac{4}{23}+\dfrac{5}{21}-\dfrac{4}{23}-\dfrac{5}{21}\)
\(=\left(\dfrac{16}{21}+\dfrac{5}{21}-\dfrac{5}{21}\right)+\left(\dfrac{4}{23}-\dfrac{4}{23}\right)\)
\(=\dfrac{16}{21}+0+0\)
\(=\dfrac{16}{21}\)
\(\dfrac{16}{21}+\dfrac{4}{23}+\dfrac{5}{21}-\dfrac{4}{23}-\dfrac{5}{21}\)
\(=\left(\dfrac{16}{21}+\dfrac{5}{21}-\dfrac{5}{21}\right)+\left(\dfrac{4}{23}-\dfrac{4}{23}\right)\)
\(=\left(\dfrac{16+5-5}{21}\right)+\left(\dfrac{4-4}{23}\right)\)
\(=\dfrac{16}{21}+0\)
\(=\dfrac{16}{21}\)
(23)/(23)+(5)/(23)+(19)/(21)-(5)/(23)+0,7+(2)/(21)
- ( 12 + 21 - 23 ) - ( 23 - 21 + 10 )
- ( 12 + 21 - 23 ) - ( 23 - 21 + 10 )
= (- 10) - 12
= -22