Answer
$0.438~in$
Work Step by Step
We have $4$ numbered divisions on the barrel:
$4 \times 0.100~in = 0.400~in$.
We have $1$ small division on the barrel:
$1 \times 0.025 ~in= 0.025~in$.
The head reading is $13$:
$13\times 0.001~in= 0.013~in$.
The total measurement is:
$0.438~in$.
