48. We denote the maximum dimension (side length) of each transistor as
max
, the size of the chip as A,
and the number of transistors on the chip as N . Then A = N
2
max
. Therefore,
max
=
A
N
=
(1.0 in.
× 0.875 in.)(2.54 × 10
−2
m/in.)
2
3.5
× 10
6
= 1.3
× 10
−5
m = 13 µm .