Frequency Table (Histogram)
Bins	Midpoint	Abs. Frequency	Rel. Frequency	Cumul. Rel. Freq.	Density
[40,60[	50	2	0.027778	0.027778	0.001389
[60,80[	70	20	0.277778	0.305556	0.013889
[80,100[	90	19	0.263889	0.569444	0.013194
[100,120[	110	28	0.388889	0.958333	0.019444
[120,140[	130	2	0.027778	0.986111	0.001389
[140,160[	150	0	0	0.986111	0
[160,180]	170	1	0.013889	1	0.000694