+389 The ratio of the number of junior high students to the number of senior high students in a school is 7 to 9. If there are 100 more senior high students than junior high students, how many junior high students are there?
+128475 Let N be the number of junior high students. Then 100 + N = the number of senior high students.
And we are told that :
N / [100 + N ] = 7/ 9 cross multiply
9N = [100 + N] * 7 simplify
9N = 700 + 7N subtract 7N from both sides
2N = 700 divide both sides by 2
N = 350 and this is the number of junior high students....the number of senior high students is 450.....and their ratio is 350 / 450 = 7 /9
+128475 Let N be the number of junior high students. Then 100 + N = the number of senior high students.
And we are told that :
N / [100 + N ] = 7/ 9 cross multiply
9N = [100 + N] * 7 simplify
9N = 700 + 7N subtract 7N from both sides
2N = 700 divide both sides by 2
N = 350 and this is the number of junior high students....the number of senior high students is 450.....and their ratio is 350 / 450 = 7 /9
