Question

A car manufacturer claims that the miles per gallon (mpg) of all its midsize cars can be modeled with a normal model with N(33, 1.70).

1. What proportion of cars have miles per gallon less than 31.2 [P(x ≤31.2 mpg)]?

2. What proportion of cars will have miles per gallon greater than 36 [P(x ≥36 mpg)]?

3. What proportion of cars will have miles per gallon less than 30[P(x ≤30 mpg)]?

4. What proportion of cars will have miles per gallon between 32 and 35 [P(32 mpg ≤x ≤35 mpg)]?

5. How many miles per gallon do the top 10% of the midsize cars have?

Answer 1