Evaluate -Z + 7.49 for Z = -7.1

answer: 33 ( approx)

step-by-step explanation:

since, in the linear regression formula, the slope is the a in the equation y = b + ax ( by comparing it with the general equation of line y = mx + c )

where,

here given table is,

price ($), x   :           18         23       25       29       30       33

pairs sold, y :         16         13         10       8         6       2

so, ,   ,   ,

and   ,

thus, slop of the given line is,

⇒  

⇒   ≈ 33

we need to divide the number of toy dinosaurs, 156, by the number of brothers, 4:

in order to estimate, we can use compatible numbers:

156 ÷ 4

  ↓

160   ÷ 4 = 40        

the correct answer is a).