By looking at the equation of the least-squares regression line, you can see that the correlation between height and arm span is

a. greater than zero.

b. less than zero.

c. 0.93.

d. 6.4.

e. Can’t tell without seeing the data.

The regression line is:

$\stackrel{⏜}{y}=6.4+0.93x$

The formula used:$b=r(\frac{s_y}{s_x})$

The slope and correlation coefficient have the following relationship:

$b=r(\frac{s_y}{s_x})$

The slope of the least-squares line is b, the sample correlation coefficient is $r$and the sample standard deviations for the variables $X$and $Y$are $s_x$and $s_y$respectively.

The ratio $\frac{s_y}{s_x}$is always positive since the standard deviation of any random variable cannot be negative. As a result, the sample correlation coefficient is proportional to the slope of the least-squares line. The sign of the slope and correlation coefficient will always be the same.

The slope of the least square line is positive in this case. As a result, the correlation will be positive, i.e. greater than $0$

Hence, the correct option is (a).