=( 7*5*39)/(13*14*15)
=(7*5*3*13)/(13*7*2*5*3)
=1/2
\(\frac{7}{13}x\frac{5}{14}x\frac{39}{15}\)
\(=\frac{7x5x39}{13x14x15}\)
\(=\frac{7x5x13x3}{13x7x2x5x3}\)
\(=\frac{1}{2}\)
Tinh tong sau bang cach hop ly:
B = 5/2.1 + 4/1.11 + 3/11.2 + 1/2.15 + 13/15.4
Ghi ca cach lam nhe ! Ai nhanh nhat, dung nhat tick lun !!!!!!
tinh bang cach hop li
a, 3/7+2/9+5/9+-9/10
b, 3/4+-1/7+14/7+-6/7+32/28
thuc hien phep tinh bang cach hop ly(neu co the) a)248:{[(368+232):120-3]+122}+2011 b) -243+(319:314+28:25)
Bai 1 : Viet tap hop A cac so tu nhien lon hon 4 va ko vuot qua 7 bang hai cach .
a ) Viet tap hop cac so tu nhien khac 0 va ko vuot qua 12 bang hai cach .
b ) Viet tap hop M cac so tu nhien lon hon hoac bang 11 va ko vuot qua 20 bang hai cach .
c ) Viet tap hop M cac so tu nhien lon hon 9 ,nho hon hoac bang 15 bang 2 cach .
d ) Viet tap hop A cac so tu nhien ko vuot qua 30 bang 2 cach .
e ) Viet tap hop B cac so tu nhien lon hon 5 bang 2 cach .
f ) Viet tap hop C cac so tu nhien lon hon hoac bang 18 va ko vuot qua 100 bang 2 cach .
Ai lam nhanh minh se tick cho nha ,minh can gap .
119. Tinh bang 2 cach:
a) 15 x 12 - 3 x 5 x 10
b) 45 - 9 x (13 + 5)
c)29 x (19 -13) - 19 x ( 29 - 13 )
Giai ca 2 cach ho mk.Ca 3 phan.Cam on
tinh bang hai cach
A)15 nhan 12-3nhan 5 nhan 10
B)45-9 nhan (13+5)
C)29 nhan (19-13)-19 nhan (29-13)
tinh bang cach hop ly
21x35x3x25x7
Tinh tong sau bang cach hop li nhat: (1+3+5+...+99)-(2+4+6+...+100)
Tinh bang cach hop li
-1911-(1234-1911)