The positive, negative and zero sequence reactances of a Y$-$connected synchronous generator are $0\mathrm{.}2p.u.,0\mathrm{.}2p.u.$ and $0\mathrm{.}1p.u.$respectively. The generator is on open circuit with a terminal voltage of $1p.u.$ Find the minimum value of inductive reactance, in p$.$u$.,$ required to be connected between neutral and ground so that the fault current does not exceed $3\mathrm{.}75$ p$.$u$.$ if a single line to ground fault occurs at the terminals. $($Assume fault impedance to be zero$)$