Answer
a. 0.193
b. 0.507
c. 0.067
d. 0.633
Work Step by Step
a. P(human ecology) = $\frac{43}{223}$ = 0.193
b. P(firstborn) = $\frac{113}{223}$ = 0.507
c. P(firstborn and human ecology) = $\frac{15}{223}$ = 0.067
d. P(firstborn or human ecology)
= P(firstborn) + P(human ecology) - P(firstborn and human ecology)
= 0.193 + 0.507 - 0.067
= 0.633
