Equation Step
8t + 16c = 400
given
8t + 160 - 160 - 400 — 160
subtract 16c from both sides
8t = 400 – 16t
Combine like terms
Divide by 8 on both sides
Simplify

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