A population of mice on dark soil has 40 dark mice and 60

Question

EVE 100-Fall Quarter 2015 - HW4

1. A population of mice on dark soil has 40% dark mice and 60% light mice at the start of the year. Dark mice blend into the soil and avoid predation; they have a 75% chance of surviving the year. Light mice stand out and are easy for predators to spot; they have a 50% chance of surviving the year. What are the proportions of dark and light among mice that survive the year? Show your work.