In a parade square,
29 of the students wore scarves. After 387 students who wore scarves entered the parade square, the percentage of students who wore scarves increased to 70%. How many students in the parade square did not wear scarves?
|
Wore scarves |
Did not wear scarves |
Before |
2x3 = 6 u |
7x3 = 21 u |
Change |
+ 387 |
|
After |
7x7 = 49 u |
3x7 = 21 u |
70% =
70100 =
710The number of students who did not wear scarves remains unchanged. LCM of 7 and 3 is 21.
Number of students who wore scarves and left
= 49 u - 6 u
= 43 u
43 u = 387
1 u = 387 ÷ 43 = 9
Number of students who did not wear scarves
= 21 u
= 21 x 9
= 189
Answer(s): 189