You roll a standard number die. what is the probability of rolling a number less than 5?

Suppose a man is heterozygous for heterochromia, an autosomal dominant disorder which causes two different‑colored eyes in an individual, produced 25‑offspring with his normal‑eyed wife. of their children, 15 were heterochromatic and 10 were‑normal. calculate the chi‑square value for this observation.

The jurassic zoo charges $14 for each adult admission and $5 for each child. the total bill for 77 people from a school trip was $565. how many adults and how many children went to the zoo? i

Pls! does anybody know a shortcut for answering these types of questions in the future?