I'm having trouble with this problem to calculate v=c/b so I understand that c=120 however what calculation is used for determine the b is is 120/ .45 or 120/(2/100,000) or are both of these wrong? Please help

Use willingness to pay approach to calculate value of human life. Probability of a child dying in a car accident is 2 per 100,000 children. Using child car seat reduces probability of dying by 45%. If a car seat costs $120, what is the value of life?