1.in a secondary school ,the ratio of the number of teachers to the number of students is7:200.the total number of teachers & studeets is1035.
A.find the number of teachers and the number of student.
B.In april, n students leave the school to sit for a public exam.if the ratio of the number of teachers to the number of students changes to1:25,find the value of n.
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2009-01-19 6:06 am
回答 (2)
2009-01-19 6:27 am
✔ 最佳答案
A.Number of teachers : Number if students = 7 : 200
Let the number of teachers and that of students be 7k and 200 k respectively.
7k + 200k = 1035
207k = 1035
k = 5
Number of teachers
= 7 x 5
= 35
Number of students
= 200 x 5
= 1000
Ans: There are 35 teachers and 1000 students.
B.
35 : (1000 - n) = 1 : 25
35/(1000 - n) = 1/25
1000 - n = 35 x 25
1000 - n = 875
n = 125
=
2009-01-19 5:40 pm
A. The number of teachers is
1035 * 7 / (7+200)
= 35
The number of student is
1035 * 200 / (7+200)
= 1000
B. The value of n is
35 / (1000-n) = 1 / 25
35 * 25 = 1000 - n
875 = 1000 - n
n = 125
1035 * 7 / (7+200)
= 35
The number of student is
1035 * 200 / (7+200)
= 1000
B. The value of n is
35 / (1000-n) = 1 / 25
35 * 25 = 1000 - n
875 = 1000 - n
n = 125
參考: own working
收錄日期: 2021-04-29 18:14:47
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