Now we have a three by three table here. So one way to think about it, it's the number of rows minus one times the number of columns minus one. This is two times two, which is equal to four. Another way to think about it is if you know four of these data points and you know the totals, then you could figure out the other five data points. And so now we are ready to calculate a p-value. And you could do that using a calculator and you could do that using a chi-squared table. But let's say we did it using a calculator.