Brendan practiced soccer for 1 hours on monday, 1 hours on
tuesday, 1 hours on wednesday, and hour on thursday in
preparation for the game on friday. how many total hours did
brendan practice soccer in this week?

Brendan practiced soccer for 4 hours this week.
Monday- 1 hr
Tuesday- 1 hr
Wednesday- 1 hr
Thursday- 1 hr

1+1+1+1= 4
Or
1•4=4

Her conclusion that 90% of the student body wants the colors changed is an INCORRECT conclusion. The 90% out of 100% is not referring to the total numbers of the student body.For example, 100 people are members of student body if only 50 members responded the survey, then we have:
 90% of 50 members who answered the survey said that they want the changed.