SOLUTION: The school has ten classes with the same amount of students in each class. One day the weather was really bad and many students were absent. Five classes were half full, 3 classe

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Question 391224: The school has ten classes with the same amount of students in each class. One day the weather was really bad and many students were absent. Five classes were half full, 3 classes were 3/4 full and 2 classes were 1/8 empty. A total of 70 students were absent How may students are in this school when no students are absent
Answer by ptaylor(2198) (Show Source):
You can put this solution on YOUR website!
Let x=number of students in each class
Then 10x=total number of students in school
If 5 classes are half full then we have 5x/2 students absent
If 3 classes are 3/4 full that means that (1/4)*3x students are absent
If 2 classes are 1/8 empty that means that (1/8)*2x students are absent
Now we are told that:
(5x/2)+(1/4)*3x+(1/8)*2x=70 simplify
(5x/2)+(3x/4)+(x/4)=70 multiply each term by 4 and we get:
10x+3x+x=280
14x=280
x=20----------------------number of students in each class
10x=10*20=200--------------number of student in this school
CK
100/2 + 60/4 + 40/8=70
50+15+5=70
70=70
Hope this helps---ptaylor