In a survey done by the local Better Buy store, questions were asked of 300 households that actually purchased big-screen televisions. The table at left indicates the consumer's responses to whether the television purchased was a plasma screen and whether they also purchased a DVR in the past 12 months.

Q-1a: What is the probability that a randomly selected big-screen television purchase in this sample is a purchase of a plasma-screen television?

Q-1b: What is the probability that a randomly selected household that purchased a big screen television purchased a plasma-screen AND a DVR?

Q-1c: What is the probability that a randomly selected household purchased a DVR, given that the household purchased a plasma-screen television?

Purchased DVR
Purchased Plasma Screen Yes No Total
Plasma Screen 38 42 80
Not Plasma Screen 70 150 220
Total 108 192 300