step 1
Find the mean of QB1
mean=(22+20+15+18+19+25+28+15+21+20+25+25+26+26+21+20)/16
mean=346/16
mean=21.625
step 2
Find the mean of QB2
mean=(28+18+21+16+21+25+25+21+28+21+23+19+28+18+21+28)/16
mean=361/16
mean=22.5625
therefore
mean QB2 > mean QB1
answer is the first option
