OFDM symbol duration query

I am trying to understand the relations between OFDM symbol duration and subcarriers duration.As far as i went ,i understood that regarding W and R as total bandwidth & transmission rate of transmission respectively the duration of a distinct subcarrier is just T ,where T=N*Ts with Ts the symbol duration in the single carrier case and N # of subcarriers.Also bandwidth of a subcarrier is W/N=1/T=R/N.
So far everything is good.
What i need to clarify is:
1)Is T also the OFDM symbol duration?
2)I read continiously that period of an OFDM symbol is approximately 1/W.
How is that derived?
PLs help me clarify these,thnks!