tìm y biết :
y + 32 = 46 -7 y + 28 = 54 - 8
y + 45 = 72 - 13 y + 31 = 64 - 15
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+51+52+53+54+56+57+58+59+60+61+62+63+64+65+66+67+68+69+70=?
Tính: 647 - [ y : ( 46 + 13 + 54 ) ] = 54 - 32 + 46
647-[y:(46+13+54)]=54-32+46
=647-[ y:( 46+13+54) ]=68
=647-[y:113]=68
=647-68
=579
=579x113
=65427
Tính hợp lý:
45-58+(-45)+(+58)-3
(-57)-(-12)+3-(-57)
-(-24)-(-30)+(-24)-30+8
-(-12)+(+19)-(+12)+8-19
47-(-53)+(-47)-(+53)
-(+28)+32-(-28)+(-34)
15-(+72)+(-15)+(+72)
20-(+46)+(-25)-(-46)
28-(-32)+(-28)-32+5
-75+(-49)+(+75)+49-12
Giúp e vs ạ
45-58+(-45)+(+58)-3=45-58-45+58-3=(45-45)+(58-58)-3=-3
(-57)-(-12)+3-(-57)=-57+12+3+57=(-57+57)+12+3=15
-(-24)-(-30)+(-24)-30+8=24+30-24-30+8=(24-24)+(30-30)+8=8
-(-12)+(+19)-(+12)+8-19=12+19-12+8-19=(12-12)+(19-19)+8=8
47-(-53)+(-47)-(+53)=47+53-47-53=(47-47)+(53-53)=0
-(+28)+32-(-28)+(-34)=-28+32+28-34=(-28+28)-(34-32)=-2
15-(+72)+(-15)+(+72)=15-72-15+72=(15-15)+(72-72)=0
20-(+46)+(-25)-(-46)=20-46-25+46=(20-25)+(46-46)=-5
28-(-32)+(-28)-32+5=28+32-28-32+5=(28-28)+(32-32)+5=5
-75+(-49)+(+75)+49-12=-75-49+75+49-12=(-75+75)+(49-49)-12=-12
\(...=45-58-45+58-3=-3\)
\(...=-57+12+3+57=15\)
\(...=24+30-24-30+8=8\)
\(...=12+19-12+8-19=8\)
\(...=47+53-47-53=0\)
\(...=-28+32+28-34=-2\)
\(...=15-72-15+72=0\)
\(...=20-46-25+46=-5\)
\(=...28+32-28-32+5=5\)
\(...=-75-49+75+49-12=-12\)
Tính
3 * 8 + 36 : ( 6 +3 )
18 : 3 - 16 * 4 : 32
Tìm y biết :
432 : y + 54 : 6 = 7 * 45 : 5
a) \(\frac{3x8+36:(6+3)}{18:3-16x4:32} \)= \(\frac{24+36:9}{6-64:32}\)= \(\frac{24+4}{6-2}\)=\(\frac{28}{4}\)=\(7\)
b) 432 : y + 54 : 6 = 7 x 45 : 5
432 : y + 9 = 7 x 9
432 : y + 9 = 63
432 : y = 63 - 9
432 : y = 54
y = 432 : 54
y = 8
Vậy y = 8
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 * 51 * 52 * 53 * 54 * 55 * 56 * 57 * 58 * 59 * 60 * 61 * 62 * 63 * 64 * 65 * 66 * 67 * 68 * 69 * 70 * 71 * 72 * 73 * 74 * 75 * 76 * 77 * 78 * 79 * 80 * 81 * 82 * 83 * 84 * 85 * 86 * 87 * 88 * 89 * 90 * 91 * 92 * 93 * 94 * 95 * 96 * 97 * 98 * 99 * 100 bằng bao nhiêu?
( 32/46 x Y - 16/23 x 21/23) : ( 12/25 + 5/8 x 13/6 - 36/45 : 3 ) = 0
tim Y
bai nay bai lop 5 co phai hong chi
Điền dấu >, <, = vào chố chấm:
28 … 31 | 84 … 90 | 54 … 50 + 5 |
65 … 64 | 72 … 72 | 25 … 20 + 5 |
23 … 32 | 48 … 39 | 86 … 80 + 7 |
Lời giải chi tiết:
28 < 31 | 84 < 90 | 54 < 50 + 5 |
65 > 64 | 72 = 72 | 25 = 20 + 5 |
23 < 32 | 48 > 39 | 86 < 80 + 7 |
28 < 31 | 84 < 90 | 54 < 50 + 5 |
65 > 64 | 72 = 72 | 25 = 20 + 5 |
23 < 32 | 48 > 39 | 86 < 80 + 7 |
Tìm các số x và y biết
1) 4/x= y/21=28/49. 2) x/2=3/y. 3)42/54=7/x
4) 2/3 =y/15. 5)6/10 = 3/x =y/20
\(\dfrac{4}{x}=\dfrac{y}{21}=\dfrac{28}{49}=\dfrac{28:7}{49:7}=\dfrac{4}{9}\\ Vậy:x=\dfrac{4.9}{4}=9\\ y=\dfrac{4.21}{9}=\dfrac{28}{3}\)
\(\dfrac{x}{2}=\dfrac{3}{y}\\ \Leftrightarrow x.y=2.3=6\\ Vậy:\left[{}\begin{matrix}\left(x;y\right)=\left(1;6\right)=\left(6;1\right)\\\left(x;y\right)=\left(2;3\right)=\left(3;2\right)\end{matrix}\right.\)
\(3,\\ \dfrac{42}{54}=\dfrac{42:6}{54:6}=\dfrac{7}{9}\\ \dfrac{42}{54}=\dfrac{7}{x}=\dfrac{7}{9}\\ Vậy:x=\dfrac{7.9}{7}=9\)