data tomato;
input fert $ yield @@;
cards;
a 29.9 a 11.4 a 25.3 a 16.5 a 21.1
b 26.6 b 23.7 b 28.5 b 14.2 b 17.9 b 24.3
proc print data=tomato;
title 'yield data from two fertilizers';
run;
proc ttest data=tomato;
class fert;
var yield;
title 'hypothesis test for difference in mean yield';
run;