There are 20 girls and 15 boys in a class.
(a) What is the ratio of number of girls to the number of boys?
(b) What is the ratio of number of girls to the total number of students in the class?
(a) From the question, the number of girls = 20
and, the number of boys = 15
Now,
Total number of students = Number of girls + Number of boys
= 20 + 15
= 35
Hence, the ratio of number of girls to boys
= 
= 
= 
Thus the ratio of girls to boys is 4:3
(b) The strength of girls = 20
The strength of boys = 15
Now, Total number of students = Number of girls + Number of boys
= 20 + 15 = 35
Hence,
The ratio of the number of girls to the total number of students can be calculated as follows:
= 
= 
= 
Thus, the ratio of number of girls to the total number of students is : 4: 7
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