UCLN la 4
UC la:+/-(1,2,4)
so hs do la BC cua 6va11 tu khoang 50-100 suy ra so hs la 66 em
Goi số học sinh do la x (50<hoac=x<hoac bang 100)
Ta co x chia het cho 6
x chia het cho 11
=>x thuoc BC(6,11)
Lai co : 6=2.3 11=11
=> BCNN(6,11)=66
=>BC(6,11)=(0,66,132,198,.....)
vi x nam trong khoang tu 50 den 100 => x=66
Vay co 66 hoc sinh
(
Ta co 12=2^2.3
16=2^4
36=2^2.3^2
=> UCLN ( 12,16,36)=2^2=4 => UC ( 12,16,36)= + hoac- (1,2,4)