Question

A school has 630 students. The ratio of the number of boys to the number and girls is 3:2. This ratio changes to 7:5 after the admission of 90 new students. Find the number of newly admitted boys

Answer 1

The total number of students in school=630
let the ratio be=x
number of boys=3x
number of girls=2x
firstly we have to find the value of x
2x+3x=630
5x=630
x=630/5
x=126
Now we have to put the value of x
3x=3×126=378
2x=2×126=252
the new admitted student is 90
now the ratio of total admitted student
boys=7x
girls=5x
now we have to find the number of students
7x+5x=720
12x=720
x=720/12
x=60
now we have to put the value of x
boys=7x=7×60=420
Before the admission the number of boys=378
After the admission the number of boys=420

we have to find the newly admitted boys
420-378=42
hence the newly admitted boys is 42

Answer 2

Answer:

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