For the following data:

The sample statistic t follows t-distribution with 'm' degrees of freedom, then m is equal to

7

The correct answer is Option (3) → 7 **

Given two samples:

Sample 1: $n_1=4,\;\bar{x}_1=40,\;s_1=8$

Sample 2: $n_2=5,\;\bar{x}_2=50,\;s_2=10$

Degrees of freedom for two-sample t-statistic (independent samples, unequal variances) is:

$m = n_1 + n_2 - 2$

$m = 4 + 5 - 2 = 7$

$m = 7$