Question

48. In successive class frequencies are added bottom to top. a) Relative frequency b) Frequency density c) Less than type cumulative frequency d) More than type cumulative frequency​

Answer 1

Answer:

Probability of Certain Ranges Occurring

Figure 3.4 shows the relative frequency distribution of tumor sizes of 115 liver cancers. A normal curve with the same mean (2.77 cm) and standard deviation (1.01 cm) is superposed. Let us denote mean by μ and standard deviation by σ for shorthand. We ask what percent of tumors are larger than 5 cm. If we are willing to accept the normal curve as the probability distribution of liver tumor sizes, the probability of a tumor larger than 5 cm is the proportion of curve greater than 5. The value 5 cm lies 5−2.77=2.23 cm to the right of μ. How many σ is that? 2.23/1.01=2.21σ to the right of μ. Table 6.1 shows the area in the right tail to the right of 2.20 is 0.014. About 1.4% of tumors are larger than 5 cm.