Let page table size be x:
3rd level page table will have $\frac{2^{46}}{x}*2^{2}$=$\frac{2^{48}}{x}$
2nd level page table will have $\frac{2^{48}}{x^{2}}*2^{2}$=$\frac{2^{50}}{x^{2}}$
1st level will have $\frac{2^{50}}{x^{3}}*2^{2}$=$\frac{2^{52}}{x^{3}}$
now page size = page table size
x=$\frac{2^{52}}{x^{3}}$
$x^{4}=2^{52}$
x= $2^{13}$
Page size= page Table size = 8Kb
