Let p1 and p2 be the number of antinodes of both wires.
Fundamental frequency remains the same for both wires.
n1=n2
T→same
r→same
l→same
n=2lpπr2ρT
From the above equation, we have
ρ1p1=ρ2p2
→p2p1=ρ2ρ1
The ratio of antinodes is p2p1=21.