If indeed 15% of the population of Texas is positive that would be 29 millionx0.15 = ~ 4.4 million people. There total reported fatalities as of today are 3046, or roughly a tenth those of New York, a State with only two-thirds the population of Texas.

That would mean that - as of yet - the case-fatality rate would be 3046/4,400,000 or roughly 0.07%.