Consider the following data :

A straight line trend by the method of least square is :

$y=11.6+5.2x$

The correct answer is Option (3) → $y=11.6+5.2x$

The straight line trend equations,

$y=a+bx$

$∑x=(-2)+(-1)+0+1+2=0$

$∑y=3+6+9+16+24=58$

$∑xy=(-2)(3)+(-1)(6)+(0)(9)+(1)(16)+(2)(24)=52$

$∑x^2=(-2)^2+(-1)^2+0^2+1^2+2^2=10$

$b=\frac{∑xy}{∑x^2}=\frac{52}{10}=5.2$

$a=\frac{∑y}{n}=\frac{58}{5}=11.6$

$y=11.6+5.2x$