nSample=10;nRep=10^5;
CLT.unif <- function(nSample, nRep) {
  x=matrix(runif(nSample*nRep),nrow=nSample);
  x.means<-colMeans(x)
  hist(x.means,50,main='Distribution of Means of Uniform Distribution', 
    xlab='Means', probability=T)
  x.means.dens<-density(x.means)
  lines(x.means.dens,lwd=3,lty=1,col='red')
  x2=seq(0,1,0.001);CLT=dnorm(x2,mean=0.5,sd=(sqrt(1/12))/(sqrt(nSample)))
  lines(x2,CLT,lwd=3,lty=3,col='cyan')
  legend("topright",c("Density of Actual Means","Normal Distribution"), 
   lty=c(1,3), col=c('red','cyan'),lwd=3)
}

> CLT.unif(10,100000)