3(x+6) what could the answer rlly be pls tell me?

Carlos has 4/5 of a tank of fuel in his car. he uses 1/10 of a tank per day. how many days will his fuel last?

Asurvey of 45 teens found that they spent an average of 25.6 hours per week in front of a screen (television, computer, tablet, phone, based on the survey’s sample mean, which value could be the population mean? 2.3 hours 27.4 hours 75.3 hours 41.5 hours

Combine like terms to make a simpler expression 3z+z