Can we conclude that, on the average, lymphocytes and tumor cells differ in size? The following are the cell diameters ð Þ mm of 40 lymphocytes and 50 tumor cells obtained from biopsies of tissue from patients with melanoma:

Lymphocytes 9.0 9.4 4.7 4.8 8.9 4.9 8.4 5.9 6.3 5.7 5.0 3.5 7.8 10.4 8.0 8.0 8.6 7.0 6.8 7.1 5.7 7.6 6.2 7.1 7.4 8.7 4.9 7.4 6.4 7.1 6.3 8.8 8.8 5.2 7.1 5.3 4.7 8.4 6.4 8.3 Tumor Cells 12.6 14.6 16.2 23.9 23.3 17.1 20.0 21.0 19.1 19.4 16.7 15.9 15.8 16.0 17.9 13.4 19.1 16.6 18.9 18.7 20.0 17.8 13.9 22.1 13.9 18.3 22.8 13.0 17.9 15.2 17.7 15.1 16.9 16.4 22.8 19.4 19.6 18.4 18.2 20.7 16.3 17.7 18.1 24.3 11.2 19.5 18.6 16.4 16.1 21.5 Let a ¼ :05.