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प्रश्न
The ratio of the number of girls to the number of boys in a school is 2 : 5. If the number of boys is 225; find:
(i) the number of girls in the school.
(ii) the number of students in the school.
उत्तर
Let, the number of girls in school = x
Number of boys in school = 225
According to question 2 : 5 = x : 225
⇒ 5 × x = 2 × 225
x = `(2xx225)/5` = 2 × 45 = 90
Number of girls in school = 90
Total number of student in the school = (number of boys + number of girls) = (225 + 90) = 315
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