x=c(23,27,28,28,29,30,31,33,35,36)
y=c(18,20,22,27,21,29,27,29,28,29)
cor(x,y)
cor(x,y,method="pearson")
cor(x,y,method="spearman")

#find rank coreelation coefficient of the following
x=c(44,49,52,54,47,76,65,60,63,58,50,67)
y=c(48,55,45,60,43,80,58,50,77,46,47,65)
cor(x,y,method="spearman")
cor(x,y,method="pearson")

x=c(175,168,170,171,169,165,165,160,180,186)#height
y=c(80,68,72,75,70,65,62,60,85,90)#weight
#using inbuilt function
cor(x,y)
m1=lm(formula=x~y)
m2=lm(formula=y~x)
m1
m2
#calculate height when weight =65
 h1=(65*0.7662)+115.2002
 h1
 #calculate weight when height=170
 w1=170*1.266-143.696
 w1
 #usin formula
#cov(x,y)/sdx,sdy

var(x)
var(y)
a=sqrt(var(x))
b=sqrt(var(y))
r=cov(x,y)/(a*b)
r