Same Operators, Two Layouts

A workshop redesigns an assembly station and wants to know whether the new layout has cut assembly time. The same five operators are timed once on the old layout and once on the new one:

Operator	Old layout (min)	New layout (min)
A	$12.5$	$12.0$
B	$12.1$	$12.0$
C	$13.0$	$12.5$
D	$12.8$	$12.7$
E	$12.4$	$12.1$

Because every operator is measured twice, the analyst runs a paired t-test on the per-operator differences $d = \text{old} - \text{new}$ , testing

$H_0: \mu_d = 0 \qquad \text{against} \qquad H_a: \mu_d > 0$

The population standard deviation is unknown, so estimate it from the differences using the sample standard deviation with the $n - 1$ divisor.

What is the value of the t-statistic? Round your answer to 2 decimal places.

Same Operators, Two Layouts

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