If it's the same strings it came with they're probably a set of D'addario 9-42 nickel wounds, most Ibanez's are strung with those as standard.
R.I.P. My Signature. Lost to us in the great Signature Massacre of 2014.

Quote by Master Foo
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my RG321MH has 10-46 stock. the manual also says the string gauge for your guitar.
Ibanez RG321MH (Air Classic/Tone Zone)
Fernandes Telecaster (Twang King/stock bridge pickup)
Blackstar HT-20 (Scumback 55 speaker/ Tung Sol tubes)
TC Electronic Nova Repeater
Lava Cables Clear Connect, Soar and Mini ELC
Yeah, my Ibanez SA120 was shipped with Extra Light D'addario strings.

I can drop mine 2 whole steps down, but it sounds a little buzzy.