size(200,0); pair z0=(0,0); pair z1=(2,0); pair z2=(5,0); pair zf=z1+0.75*(z2-z1); draw(z1--z2); dot(z1,red+0.15cm); dot(z2,darkgreen+0.3cm); label("$m$",z1,1.2N,red); label("$M$",z2,1.5N,darkgreen); label("$\hat{\ }$",zf,0.2*S,fontsize(24pt)+blue); pair s=-0.2*I; draw("$x$",z0+s--z1+s,N,red,Arrows,Bars,PenMargins); s=-0.5*I; draw("$\bar{x}$",z0+s--zf+s,blue,Arrows,Bars,PenMargins); s=-0.95*I; draw("$X$",z0+s--z2+s,darkgreen,Arrows,Bars,PenMargins);