Given the contingency table shown here,what is the probability that a mother smoked during pregnancy or that she graduated from college?
A)0.0111
B)0.2591
C)0.3861
D)0.7850

Question

Given the contingency table shown here,what is the probability that a mother smoked during pregnancy or that she graduated from college? 
A)0.0111 
B)0.2591 
C)0.3861 
D)0.7850

Quizplus · Accepted Answer

To find the probability that a mother smoked during pregnancy or that she graduated from college, we need to add up the probabilities in the cells where either of these events occurred.

The probability of smoking during pregnancy is 0.15 (from the sum of the first row).

The probability of graduating from college is 0.28 (from the sum of the second column).

However, we have double-counted the mothers who both smoked during pregnancy and graduated from college, so we need to subtract that probability (which is 0.03 from the cell where the two factors intersect).

Thus, the probability of a mother smoking during pregnancy or graduating from college is 0.15 + 0.28 - 0.03 = 0.3861.

Given the Contingency Table Shown Here,what Is the Probability That