Class lower limits Midclass Class upper limits Freq f RF Low Mid High
13 15.5 18 4 0.02 0.26 0.31 0.36
18 19.5 21 22 0.11 1.98 2.15 2.31
22 23.5 25 37 0.19 4.07 4.35 4.63
26 27 28 30 0.15 3.9 4.05 4.2
29 32 35 40 0.2 5.8 6.4 7
36 40.5 45 27 0.14 4.86 5.47 6.08
46 55.5 65 40 0.2 9.2 11.1 13



200 1 30.07 33.82 37.57

+1 Chose coherent bins







+1 Correct frequencies ( 4, 22, 37, 30, 40, 27, 40)







+1 Correct sample size (200)







+1 Correct relative frequencies







+1 Correct relative frequency sum (1.00)







+2 Mean age between 30 and 38







7 points
















+1 Mean age quoted as a range (between 30 and 38)