Question

A team of biologists is studying a population of 800 fish they find that 15 out of every 75 fish are more than 30cm long based of this result how many fish in the population are 30 cm or less in length

Answer 1

Answer:

640

Step-by-step explanation:

Since 15 out of every 75 fish are more than 30 cm long, the probability of finding a fish more than 30 cm is P(x > 30) = 15/75 = 1/5.

The probability of finding a fish 30 cm or less is P(x ≤ 30) = 1 - P(x > 30)

= 1 - 1/5

= (5 - 1)/5

= 4/5

Since we have 800 fish and the probability of finding a fish 30 cm or less is P(x ≤ 30) = 4/5, then the number of fish in the population that are 30 cm or less in length are 800 × P(x ≤ 30) = 800 × 4/5

= 160 × 4

= 640

So, 640 fish in the population are 30 cm or less in length