In a test, correct answers carry +3 marks and wrong answers carry -1 marks. Ramesh answered all the questions. He scored 79 marks, though he maked 5 mistakes. Find the number of correct answers?

Don't know how to find x given these segment lengths

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

What is the greatest number of parts of a circle that can be formed by cutting the circle with 7 straight cuts? (note: the parts do not have to be equal in size)