The polynomial p(x)=x^3+2x-11 has a real zero between which two consecutive integers?

Given:
p(x) = x³ + 2x - 11

Create a table of p(x) versus x for integral values of x from -2 to 2.
  x    p(x)
---  
-2   -23
-1    -14
 0    -11
  1    -8
  2     1

A change in sign occurs for p(x) in the interval 1 ≤ x ≤ 2.
Therefore a real zero exists in this interval.

Between 1 and 2.
A real zero of p(x) occurs between x = 1  and x = 2.

There is 240 red cars and there is 400 blue cars because 240/3=80 and 80*5=400